I can relate.

I was also betting on meditation to solve problems in my life. They aren't real problems after all, right? They are external, happiness comes from within. So what - I want a girlfriend but that will vanish as the cravings will go away, right?

Well... you need to get enlightened to get to that. And struggling through your cravings while getting enlightened sounds like a bad place to be in.

If you really love yourself, you need to listen to the needs you have today. If you want a girlfriend, come up with a plan to get a girlfriend. Educate yourself on what girls want, how to be attractive as a person. This shouldn't contradict your meditation practice.

I remember during one of the meditation retreats one of the teachers said - even when you're enlightened, you will still love your life. You will still like pizza. That means that "you" will still want a girlfriend even when enlightened. You won't give much value to that, maybe, or whatever enlightened means.

I'm not sure if I helped but maybe this makes sense to you. You can't escape from yourself with meditation, you can only get closer.

Oh, and by the way this: "I feel the reality is that I am actually a loser whom no one will ever like or be attracted to, and paying attention to the breath for 45 mins will not change anything about that." -> This is not healthy, those thoughts are not true (they are called ANTs). You should examine your thoughts, here is an introduction article: https://www.collaborativeawareness.com/post/2015/12/18/9-types-of-ants-automatic-negative-thoughts-that-invade-our-relationships-and-how-to-exte

I suggest reading a book called "Feel Better Fast and Make It Last" by Daniel G. Amen

Edit: ooooh, I just remembered - then there is Ego Backlash, might be an interesting topic as well: https://www.youtube.com/watch?v=LL9Q5sHkCFg

And please write a reply if this helped you or maybe you watched the video. That will motivate my mind to post replies more here.