Failure in the moral life is not rare. As the saying goes, “The saints were not people who never fail, but the people who kept getting up.”
I also don’t believe that our every difficulty is something “sent by God”. Rather, most of our difficulties are the result of the Fall. I do believe that God can transform every difficulty into a victory. The Cross didn’t come from God; the Cross came from the Fall. The Passion and Resurrection is what God can do with crosses. Hope tells us that our tries, buried through baptism in the victory of Christ, will likewise be transformed by the power of God.
OP, you say you are not strong enough to carry your own cross. You don’t have to be. You don’t have to never fall. You have to want to never fall. Keeping wanting that, keep trying, and you will be taken care of.
Also, realize that most straight men also struggle with aspects of their sexuality that are less than pure. They look at women with lust in their hearts. Some have porn addictions, some have a very hard time being faithful to one woman. The man who marries one woman and never has a thought or temptation for another exists, but he’s not the majority, particularly not in an age like ours, where the glamour of evil can beckon so openly and constantly. You have a particularly difficult problem, but you aren’t alone.
Remember, too, that Our Lord himself never married. He was in a culture in which a man who didn’t marry was judged, sometimes very harshly. It is entirely possible that he lived with accusations that he was homosexual. You can imagine how hard it would have been for him to have the desires any man might have, and yet know that his call was to remain as he was, regardless of what others said or whispered about him, regardless of how they might have tried to make him into something he could not be. Maybe that will help you to see that he understands what you are going through very well, indeed. Likewise, Our Lady and St. Joseph were married, but completely abstinent, because of her unique place in salvation. They know what it is to see the world living an ideal that does not apply to you. It might help you to believe that God can create an ideal of God’s own making around you, something no one would imagine, something that will eternally shine as a splendid thing.
You were created through him, too; realize that he understands you better than you understand yourself. He understands all your struggles, and he knows how hard you have struggled to please him rather than himself. That is the kind of struggle that is pleasing to God, not because it is hard or because God loves suffering, but because God cannot but be pleased by someone who will go to such lengths because love of God demands it.
