They are different, but related. Especially as time goes on and everyone else gets more involved with their families. And as you get older it becomes less and less socially acceptable to be alone to the point where people want to be friends with you less and less, so then you end up truly alone.

I'm really worried for you that you've made that the crux of your life, to the point that you'll kill yourself. And by 30? Do you actually have reason to believe that, or is it just something someone told you and you internalized?

No, there have been studies on this. People who are alone, especially people who live alone (i.e people who do not have romantic relationships) are far more likely to be depressed.

All I really care about personally is having a family. I don't really see the point in having hobbies or career success unless you have someone to share that with.

People, at least some people, I'd even say most, can be perfectly happy without a romantic relationship.

Well, it doesn't matter what you say because the evidence is out there that the opposite of this is true.