At least the ball is rolling & your halfway to a solution!
If she likes you initiating sex at least you have a doorway to use, instead of a locked one.
i've allowed myself to be dependent on another human being
Isn't that what a committed relationship is about? It may be a case that you feel rejected rather than dependant. You feel out in the cold, rather than hanging on her every lack of action. Look outwards to a fuller solution, not to how you feel with this at this stage as a solution will make these feelings move on.
If she feels too comfortable - how about starting again? I have heard of couples who start to date again - with or without the sex.
Or simply forget about the fun of dates & have breaks away or meals out as pennies will allow. Getting romantic can be a good tool to use as in effects you are starting to become strangers, which can happen as we grow together.
I don't think that your issue is one of exploring fantasies but more that of gaining her interest to be more active with the intimacy so you may need to recapture some of that energy that was there at the start!
Failing that there is always couple counselling. You havn't mentioned if you have any children, or how old etc as they can also be a drain on energy & it can be hard to get romantic with little ears about.
Lovely speaking to you & I wish you well