I have depression too, and it has played a part in my "interest", in both intense interest and intense disinterest.
You may simply be coming into a different kind of faith. I don't know if this is an appropriate comparison, but I can compare it to teenage puppy love, compared to adult marital settling down love. Maybe a better one, a relationship with parents that goes through trials and comes through.
No matter how old you get, aging always means changes, and changing can involve your relationship with God. Right now I have a friend who is exploring why God doesn't always answer prayers, and at this point I've been through that and it's a non-issue for me.
Depression can play a big part in this because of how you perceive things around you. When I'm not depressed, going for a walk can be the most pleasant and wonderful thing ever. When I am depressed it is boring, seen this already, barely there, not paying attention. If a relationship with God seems co-dependent, you are just not receiving the good parts, and that could be no fault of your own.