How to stop worrying and feeling negative?

I feel like I’ve been negative my whole life and this time it needs to stop because I’m exhausted from overthinking myself to the point where the ones I care about can no longer put up with me.

I have chronic anxiety and depression, so I can’t stop worrying about what will happen next, what others think about me, am I too negative for them, why doesn’t anyone like me genuinely if I don’t perform and try to put on a happy smile? Thoughts like that make me view the future through grey lenses and bring down my self-esteem which can’t be any lower already. I tried going to the gym, picking up a hobby, meeting up with friends and vent with them, telling myself that this life is worth living and there are so many things to explore, that humans are meant to have flaws so if I’m imperfect that’s fine… It worked for some days, on other days my disturbing thoughts return and I felt down again. Yesterday I was really sad that because of my mood I could not have a decent conversation with my partner and he said I’m bringing him too much negativity in the past time. I want to change myself for the better, not only to stay with this man but also to release myself from stress. I just don’t know how :(