I haven’t been myself in a while

(TW: Death) I’m a 29m and I feel myself sinking deeper and deeper into isolation. I’ve been introverted my whole life but when I got into my 20s I managed to control my loner tendencies and became more comfortable in social settings. A lot of dumb things would happen interacting with people but it never got to me as much as it does now. I can’t stand it. I thought I was depressed before but now it’s to the point where I dread waking up everyday. I’ve never been in a complete relationship with a woman but I’ve engaged in sex with them and every time they would want to pursue something more than fwb I would panic and come up with excuses. It’s a terrible personality trait, I know, but I don’t know where it stems from and now I’m paying for it. And then a few months before the pandemic, a close friend of mine who had been in this fwb situation I created (she eventually moved on and found someone to be in a healthy relationship with) ended up dying of an accidental overdose. Later that year one of my older brothers was murdered, I lost another friend who died fighting someone, beginning of 2021 my cousin was murdered, my dad was also diagnosed with cancer (multiple myeloma) and then in October he ended up passing away due to the medication giving him a whole different disease on top of the health problems he was already dealing with. And now here I am in 2022, apathetic and just going through the motions. I’m not using my loss as an excuse, I’m just really hurt and confused. I work full time at a decent paying job for the work that is required. But I feel like my coworkers just think I’m weird and awkward even though a lot of them know that my dad recently passed away. So a lot of times I don’t even bother trying to be social because they just think i’m doing it just to do it or I don’t really care. And maybe part of that is true, but I don’t want to be that way forever. I know there’s a way to heal from these types of situations but I’m just not seeing the light at all. I did therapy for most of last year and he suggested joining a support group but at this point I don’t even know which one would help my situation. What do I do from here?

TL:DR – I’ve been antisocial and mourning for like 2 years and I need advice.