You sound like me only 12 months ago OP.
I lived my day in a constant worry, constantly dreading bad news, my partner was going to leave me, I would get home and he would have some bad news or tell me I'd done something wrong. I'd worry about money, my job, my friends, how much houses/mortgages would cost in 10 years time, everything! I'm not sure what it was - paranoia/anxiety/depression? This was my life for as long as I'd known it. Everything was always crap, my life my partner everything.
I tried anti-depressants and therapy - wasn't for me but it's always worth exploring.
I'm not sure what changed in my life - maybe all I needed to do was make better life choices. Leave my partner, take control of my life? (I'm not saying this is the same for you). I'm not sure. But anyway.
Things just started getting better, I taught myself to find a positive in every negative thought I had. I left toxic friendships/relationships. Basically, I took back control of my life and things have never been better. I don't ignore negative thoughts or worries, because they can be real life threats. But I ALWAYS focus more on the what I can control, what the positives are and how, if the worst happens, I can change that outcome to a good one.
I've never been happier OP, you WILL get there. It is possible I promise! I still worry about stuff, that's normal and anyone who says they live their life with no worries is lying.
Please don't take my little story as how I feel your life is or that you are making poor choices, this was just the case for me. But I promise you, one day, you will find the happiness and peace you need/want.