Wow! Thank you, everyone. There is so much good advice here; thanks for the counsel, the stories, and quotes from church fathers. All of it is so helpful. There's a lot for me to digest. One thing that comes across loud and clear is the need for patience, to stop trying to feel anything, rely solely on seeking to do God's will, and not seeking to experience anything. Rather, I must externalize, serve others, seek to glorify God, purifying myself to be a receptacle for His graces, which He will bestow according to His will.
Some of the things people said perfectly illustrate what I think is the flaw in the tradition I was raised in. "If you didn't 'feel' the presence of God, then you weren't 'right' with God." "If it's up to me, if I don't jump through the hoops or have the requisite experiences or feelings, then I'm to blame." Exactly. That is just how Mormons talk. That's how I used to talk. The quote from Theophan the Recluse is so descriptive of people in my life who have talked like that when I told them I've never felt God's spirit: "When the query arises 'Is this it?', make it your rule once and for all mercilessly to drive away all such questions as soon as they appear. They originate from the enemy. If you linger over this question the enemy will pronounce the decision without delay, 'Oh yes, certainly it is - you have done very well!' From then on you stand on stilts and begin to harbor illusions about yourself and to think that others are good for nothing. Grace will vanish: but the enemy will make you think that grace is still with you. This will mean that you think you possess something, when really you have nothing at all." I don't want to be harsh or judge the people in my life who mean well but tell me I must have done something wrong, because "they've certainly received a spiritual witness that the Mormon church is true. There can be only one reason why you haven't received that witness." It does seem that what you shared from Theophan the Recluse said applies to the Mormon approach. Would it be wrong of me to suggest that the Mormon approach is a spirituality of pride? "What do I get, where's my spiritual experiences? I've done everything God asked of me, where's my reward? I was a good missionary, a good Mormon." I've certainly felt that way many times. I think I'm beginning to understand what it means to acquire an Orthodox mindset. It's all about God, not about me. These habits will be hard to root out. There's a Mormon scripture that says "I, the Lord, am bound when you do what I say. When you do not what I say, you have no promise." This sets up a relationship with God that is contractual, as if God is an equal partner. Mormons are so keen on experiencing those positive, warm feelings to support their testimonies, that they'll latch onto any positive emotions. Again, the quotes from church elders are so helpful. I love the one from Elder Ambrose of Optina about 'consoling and pleasing feelings': "These feelings are very dangerous and close to prelest, for without her having first warred with the passions, without coming to know her weaknesses and humbling herself, they are not reliable nor consoling feelings. Let them come when they do, but she must no accept them or be deceived by them, but rather consider herself unworthy." I was a Mormon for nearly 40 years, and still attend with my wife and sons (only to be with them). I have NEVER heard a Mormon talk like that when someone reports that they felt the spirit.
So..it seems the answer to rooting out the Mormonism and atheistic impulses is to stop expecting anything from God as if he owes me, stop looking for a spiritual experience, which can easily become a god in it's own right, an idol, a source of illusion and delusion, and follow the simple advice (summarizing what you all have said) of focusing externally through conscientiously following my prayer rule, turn everything into a liturgy that glorifies God, turning towards charity, giving, tending to the sick, the poor, the suffering, and looking for Christ in everyone. Hearing and accepting that advice is easy; putting into practice is hard. Lord have mercy.
Thank you so much for the advice and counsel. My Christ's blessings be upon all of you.
P.S. I had a brief phone conversation with the Orthodox chaplain in Ramstein yesterday. He's now working with me long distance to continue my journey toward chrismation. He directed me to add to my prayer rule prayers to the Theotokos, specifically for intercession in my wife's and sons' behalf, that they might one day be brought into unity with me in the Orthodox faith. It's such a relief to have a spiritual father, again. Being able to hang out here helps, too. It gives me a feeling of belonging to a local parish community.