[NeedAdvice] Is it possible to be a positive person but still not give a fuck?

If my post would be more suitable for one of the related subreddits listed in the sidebar, please let me know!

I need help changing my mentality and attitude. I've been getting more and more negative lately. It's progressed to me feeling like others are being negative and condescending towards me, but the thing is they're not.

I wrote up a draft for this post and I asked myself what kind of person I want to be. I want to be more positive and approachable. I want to feel like people really do want to be around me (a few of my coworkers have said they love being around me but I feel like I'm still very abrasive). However, I also just don't care if everybody likes me. I know the are people who don't like me and I'm ok with that. But I still want to "play the game" and be personable, if that makes sense.

I've lurked around here and started a google doc to take notes (it currently just have links I wanted to reread) so I kinda have an idea of what I should do but I still need help. For example, I don't understand how thinking happy or positive thoughts will make you a positive person? I mean logically I understand, but I battle depression (medicated and in therapy) and I can't grasp this concept.