You are correct in assuming I get a lot of letters like yours, and I'm going to be perfectly honest- I don't have a good answer.
But I think that points to the issue at hand, which may provide some ideas on what men like you can do to try and get through a difficult time.
The reason I say that is because in the letters I get from men in your situation, there seems to be this idea that there is some silver bullet, some ideal solution, some 12-step plan on getting the things you want. But there's not.
If you are a young man who's feeling lacking, it could be a multitude of things. It could be hygiene or personality or perception. It may be a demographic issue, where you're not in a place where there's enough options OR you may be in among too many options. There could be a culture around you thats harmful or that you don't vibe with, or you could be in a situation where you are not your best self.
What I'm saying is that everyones circumstances are different, which means the solutions are different and instead of trying to be a specific way and achieve specific things, you should learn how to assess your situation and find solutions that work best for you and where you are.
I think a large part of the men's loneliness epidemic is that too many men are trying to identify with an idea about the gender that was never going to include them to begin with.
Men shouldn't try to be a monolith, you are individuals. You will always think there's something wrong with you if you keep trying to fit into the this one idea of manhood.
Like any human, there is always a desire for love and affection and sex- thats perfectly natural- but plenty of young men have been driven by ideals that may not be realistic. So its important to back up and first reassess your own values. What is attractive to you, what do you really want? How are social pressures twisting your tastes around?
