You need to try to divorce the concept of "not getting sex" from the concept of "being alone". The more you're out and about, doing things with other human beings - particularly those who share your interests - the more sex you're going to get. But even if the sex takes a while to manifest, you're still having a great time doing things you love with other people, so you're not alone.
Relationships are WAY over-rated. Plus, I don't think anyone is ready for one until they've learned to be happy being single and doing their own thing. If I were in your shoes, I'd skip all the dysfunctional, codependent, messy relationship stuff and go straight to being sick of it and deciding to do something more interesting with my libidinal energy.
That's what I would do if I had a do-over. But it's only natural that you won't listen, being young and horny.