My girlfriend left me

We had an awful argument this morning, screaming, crying, throwing insults out of anger. She packed a bag and left. I don't have any close friends and my family isn't supportive of me. I divorced a few years ago, I was with my ex wife for about 12 years married for 5. I've never really lived by myself for long and I'm afraid of the silence of life destroying my mental health. My depression has been getting worse along with my anxiety the past couple of months. I've just been wanting to give up lately. I thought I'd have it together by now, like a family, good friends, maybe even supportive community or job but I don't and I think it's impossible. I'm sorry for posting here and being so dramatic, I just have no one else to talk to and feeling lost.