I can appreciate your desire to have communion with your husband in all things in your marraige the two of you were made one flesh for the salvation of both of you and your children. I am sure it is quite painful that your husband cannot share this part of your life with you and the children.
There are many things in life that do not make perfect sense to us upon first(or even seventeenth) glance, and this dogma of the Church can certainly fall into that category. Perhaps it would help to talk about the first instance of holy communion - The Lord's Supper.
I am going to quote two biblical passages, not to sound condescending or assuming that you or others are not familiar with them, but in the belief that these passages are very important to the questions at hand.
Luk 22:14 And when the hour came, he sat at table, and the apostles with him.
Luk 22:15 And he said to them, "I have earnestly desired to eat this passover with you before I suffer;
Luk 22:16 for I tell you I shall not eat it until it is fulfilled in the kingdom of God."
Luk 22:17 And he took a cup, and when he had given thanks he said, "Take this, and divide it among yourselves;
Luk 22:18 for I tell you that from now on I shall not drink of the fruit of the vine until the kingdom of God comes."
Luk 22:19 And he took bread, and when he had given thanks he broke it and gave it to them, saying, "This is my body which is given for you. Do this in remembrance of me."
Luk 22:20 And likewise the cup after supper, saying, "This cup which is poured out for you is the new covenant in my blood.
1Co 11:17 But in the following instructions I do not commend you, because when you come together it is not for the better but for the worse.
1Co 11:18 For, in the first place, when you assemble as a church, I hear that there are divisions among you; and I partly believe it,
1Co 11:19 for there must be factions among you in order that those who are genuine among you may be recognized.
1Co 11:20 When you meet together, it is not the Lord's supper that you eat.
1Co 11:21 For in eating, each one goes ahead with his own meal, and one is hungry and another is drunk.
1Co 11:22 What! Do you not have houses to eat and drink in? Or do you despise the church of God and humiliate those who have nothing? What shall I say to you? Shall I commend you in this? No, I will not.
1Co 11:23 For I received from the Lord what I also delivered to you, that the Lord Jesus on the night when he was betrayed took bread,
1Co 11:24 and when he had given thanks, he broke it, and said, "This is my body which is for you. Do this in remembrance of me."
1Co 11:25 In the same way also the cup, after supper, saying, "This cup is the new covenant in my blood. Do this, as often as you drink it, in remembrance of me."
1Co 11:26 For as often as you eat this bread and drink the cup, you proclaim the Lord's death until he comes.
1Co 11:27 Whoever, therefore, eats the bread or drinks the cup of the Lord in an unworthy manner will be guilty of profaning the body and blood of the Lord.
1Co 11:28 Let a man examine himself, and so eat of the bread and drink of the cup.
1Co 11:29 For any one who eats and drinks without discerning the body eats and drinks judgment upon himself.
1Co 11:30 That is why many of you are weak and ill, and some have died.
1Co 11:31 But if we judged ourselves truly, we should not be judged.
1Co 11:32 But when we are judged by the Lord, we are chastened so that we may not be condemned along with the world.
1Co 11:33 So then, my brethren, when you come together to eat, wait for one another--
1Co 11:34 if any one is hungry, let him eat at home--lest you come together to be condemned. About the other things I will give directions when I come.
In the epistle of St. Paul, it is shown that partaking of communion while in the midst of sin is a great danger to both body and soul. In the Orthodox Church, it is not enough to merely be baptised and chrismated in the Orthodox Church, to receive communion properly we need to have confessed our sins, fasted from the night before, and pray the preparation for communion and thanksgiving prayers.
To receive the Eucharist is be in communion both body and soul with The Holy Trinity and with the entire body of The Church. Receiving communion worthily is the most pronounced "Amen" we can make acknowledging the teachings of the Church, our own sinfulness, and that we submit our fallen nature to that of the Church in all her dogmas.
In Eastern Orthodox ecclesiology, our view is that the Orthodox Church is the One Holy Catholic and Apostolic Church and that all other groups of people that call themselves Christian are removed from the Church from one degree or another. The teaching of the Church is not that there cannot be grace outside of the Church but that the only place we can conclusively state that the grace of God resides is within the Church. Outside of that we can hope that there is much grace and even applaud the many good works done by bodies removed from the Church, but as there is one Christ there is one Body of Christ according to any and all sources of tradition we have.
The Church is for the salvation of mankind. All are called to bear their cross and become communicants within the Church. It is for this reason that we were created and that Christ was made God in the flesh. We lament those who have left the Church, and pray for their return to the Body of Christ as we pray the same for their descendants. We wait with open arms to receive any who confess that "God is the Lord and has revealed Himself to us" in the Church.
When a deacon is ordained a priest, part of the service involves having the bishop placing the consecrated bread, the Body of Christ, in the priest's hands with the statement "take this and know that you shall answer for it." The priest is responsible not only for keeping the chalice, but also for his flock. There are many reasons why the priest may refuse the Eucharist to a person, but ultimately they boil down to that person's refusal of the above confession, whether by refusal to repent for their sins, by not trusting in the teachings of the Church, or by some other manifestation.
To restate the obvious, according to the Orthodox Church communion is a literal life-or-death matter. I would like to leave you with the prayer that all Orthodox Christians pray shortly before partaking of the Eucharist as a mediation.
I believe, O Lord, and I confess that Thou art truly the Christ, the Son of the Living God, Who camest into the world to save sinners, of whom I am first. I believe also that this is truly Thine own pure Body, and that this is truly Thine own precious Blood. Therefore I pray Thee: have mercy upon me and forgive my transgressions both voluntary and involuntary, of word and of deed, of knowledge and of ignorance. And make me worthy to partake without condemnation of Thy most pure Mysteries, for the remission of my sins, and unto life everlasting. Amen. Of Thy Mystical Supper, O Son of God, accept me today as a communicant; for I will not speak of Thy Mystery to Thine enemies, neither like Judas will I give Thee a kiss; but like the thief will I confess Thee: Remember me, O Lord in Thy Kingdom. May the communion of Thy Holy Mysteries be neither to my judgment, nor to my condemnation, O Lord, but to the healing of soul and body. Amen.
It is very difficult when a marraige is based around two faiths, even if both of them are similarly Christian. I want to advise you to go talk to your priest because we are a group of semi-anonymous people who often administer the counsel of a priest without being held to the responsibility that goes along with that. From most of our perspectives, the answer of course is for your husband to convert. From the information you have given us he is obviously not an enemy of the Church as he has no problem with you continuing as a member not to mention your children. He also from your information seems to reject the belief that is held by Presbyterians that the eucharist is not the body and blood of Christ, but a ritual with just and bread and wine(grape juice) to remember his voluntary sacrifice. The standard answer is to go to your priest and he would answer the questions and see if your husband is interested in becoming a catechuman.
Life is often not as simple as we would imagine, though, as we can see just from your statement that your priest is not the most helpful in this situation, as well as perhaps other issues. There are other priests, under the same bishop and under others who are more than willing to help you in your time of need. I am not reccomending that you abandon your priest, but that option is there if your shepard will not look after his flock. We here will do our best to answer questions but please remember that we are no substitue for a priest and however helpful our advice may be, it is certainly possible that we can lead you astray.
One priest that has helped many people answer difficult questions over the internet is Fr. John Matusiak. He is even responsible for an excellent Questions and Answers
page that also has much information on this topic. Fr. John is friendly and open to questions. I would reccomend that you email him if your priest continues to not help with this issue. His email address is firstname.lastname@example.org
I hope that you find the answers you seek.