I am losing friends and everyone around me, how can I change that?

I just disgusted the hell out of people yet again when I said out loud that my cousin (Tim) is pathetic. His father, who was my uncle, was shot dead in front of him by a home invader. Tim was scarred by that and couldn’t move on for years. With anything.

He’s now 30 and just lost his virginity to somebody and when it went bad, I told him he is too shitty at it and gave trash dick. And that he should give up and die alone.

I also told him to move on from his father as I have long ago. I moved on after 3 weeks and carried on with life.

I joked about this with work friends and their jaws literally dropped. I realized then and there I’m not the best person and it’s causing me problems. How to fix this?