Was probably gonna make a throwaway account but I realise I don’t really care any more

I had a friend that I took to the clubs and I promised her mum that I’d keep her safe I wasn’t her boyfriend or anything but a long time, friend. I let her hit up a bunch of guys but for some reason she decided that she wouldn’t tell me about one of them and run-off out of the clubs and I went searching for a four hours on end I was so scared frustrated and confused and when I found the guy I beat the living shit out of him because he knew what I was. I was just a guy protecting my friends and making sure that she was safe and whoever decided to run away for no reason at all hade something sketchy going on but I feel that I was a man completely spat on and disrespected especially to someone who has been through the same things as I have sa and stuff I just wanted to get that off my chest I just feel depressed and sad and I don’t know what to do I feel like killing somebody but I won’t