this is a good post because you are being so honest and it is so hard to be really honest about sexuality if you are trying to be a spiritual person.
Perhaps sex is a little like food: if we worry about our weight and try to diet or to control our calories too much we can create all sorts of psychological hangups that only make things much worse. (bulimia etc) Perhaps the main thing is not to give sex the centre stage position it tends to crave (at least in my case) especially if our sexuality isolates us in some way. Somewhere there (centre stage) it tends to impinge on the emotional person as well and that, perhaps, is where the potential spiritual problems lie . . . and so there is a kind of inner battle line drawn between the 'physical' and the 'spiritual' which reinforces all sorts of dangerous dualistic notions about good and evil and 'purity' and the 'carnal'.
I have no answers to all of this but one thing that our sexual nature teaches us (over and over ad nauseam) is humility. (humus meaning earth; ie. being close to it). We would "reach for God and do Great Things in His name" but even the greatest saints needed a wank now and again and by heaven that puts us in our place! I love the story of St Benedict who, when he was living as a hermit and 'doing battle with the demons' was troubled over and over by a vision of naked maidens bathing (he doesnt spare on the detail). He was so determined to rid himself of this vision that he threw himself into a great patch of nettles. (He only did this once I think. Let's assume that the next time around he was gentler with himself and had a good wank instead.)
The psalmist says (lots of times) 'you remember that we are dust'. We can be sure of God's forgiveness, but the real problem is learning to forgive ourselves (and thereby others too).
In my book, this is where the real sin lies: projection. When, rather than be ruthlessly honest about our own sexual fantasies and secrets, we project that fear onto others. This can lead to bigotry and hatred in a big way as most of us already know. By the way, it is strongly my belief that stifling social 'norms' do a great deal to reinforce projection.