I feel like life is pointless without my S/O

Every day feels like it drags on forever. I don't enjoy doing mostly anything anymore, and I don't like 95% of the people I'm ever around. I feel unwanted and unwelcome pretty much everywhere, and I don't feel like there's a point to anything. The only thing that really makes me feel like life is worth living is my S/O, which I don't think is good. I've told her about this and she was understandably a little scared, because of how dependent I am on her to feel alive. I'm very scared of losing her because of this, and I still feel bad about life and all that. Is there something wrong with me? What am I supposed to do?

You are supposed to be independent and able to function and live by yourself, if you ever need to. Being so dependent on someone else is very unhealthy. Some therapy could help you learn how to do this.

I'm not a doctor but it sounds like you are very depressed. There are prescription antidepressants that may be able to help as well.

You shouldn't have told her that. It's an unnecessary burden and strain on her. It looks like emotional manipulation.

I think you should try therapy or really go deep on why you feel so bad about your life besides her and what's really missing.

Make an appointment with a doctor for an evaluation and a referral to a therapist. You can't become an emotional vampire because you are not taking care of yourself and your emotional health. That is your responsibility, not hers. In fact if you suffocate her with this, you'll lose her too.

E The only thing that really makes me feel like life is worth living is my S/O, which I don't think is good. I've told her about this and she was understandably a little scared, because of how dependent I am on her to feel alive.

Really unhealthy.

Have you sought therapy? Why don't you make an effort to make new friends? Have you looked into Meetups, volunteering, clubs, classes etc... it is YOUR responsibility to make your life full.