Getting a lot of anguish from being lonely and extremely introverted

This topic will get slightly not safe for work.

A couple months ago I was constantly breaking. Like freezing in shock from horrific thoughts that felt like experiences. I'm vegan for the animals, and I kept thinking about their situation. I had to ask for some advice from other vegans because this is a unique situation for me. They suggested self-care, so I did. 

Only, that came with drawbacks. Now I've developed a new personality where I want to be social, but I am experiencing constant depression and anxiety. I think it's linked to my loneliness and being a virgin, which I didn't realize until I began socializing online.

I went to a local support group today, 2nd ever time being outside to meet people, and I felt awkward non-stop. I'm so quiet that nobody really noticed me or cared to talk. I didn't feel awkward about having autism, I felt awkward about being so quiet and introverted that nobody wanted to talk to me. Which in turn made me feel really depressed by the end. I suffer with many issues outside of this just so you're aware. I'm really stressed out and feel useless and suicidal. So much going on in my life. 

I don't know where I belong or if I belong anywhere. I sliced up my arms a few days ago when some of the people online who I knew for months who I thought were friends, started saying I was manipulating people and acting like a victim to gain their sympathy. And I was told I was disliked and a waste of space. I don't feel welcome anywhere it seems. 

I'm still a virgin too. have struggled with dating because, nobody ever talks to me online, and I can't meet anyone in real life because anyone around my age seemingly doesn't exist. I'm lucky to be pansexual but not lucky to be male. 

I don't know what to do. Being a virgin and never experiencing physical contact, let alone love, is really taking it's toll on me. I've been in two relationships in school, and one long distance way after that. I don't know what to do. Where to go. Do I just end this agony? 

Also the NHS won't help me with my mental health problems. They've dismissed me. Called me competent. Don't know what's going on. It's sometimes too much to process. Even meeting at places feels complicated to me. I constantly need help too. Please just fucking kill me. That's the only true way anyone can help me at this point.