I need some help

Hello, my name is Jackson. I don't really post much stuff on reddit but it feels like I have no where else to turn to. My life is complete misery. It didn't used to feel like that until these last few months. A while ago I used to date this girl who We'll call "Rose". Rose was everything I had ever wanted. Pretty, funny, caring, and so so so sweet. But eventually we had broken up due to a big reason that her dad didn't allow dating. It's a whole weird ordeal but anyway, I was obviously heartbroken but eventually I thought I had gotten over her because it happend almost a year ago. A couple months back my best freind "Jax" had been talking to her on Instagram. He texted me a question "Yo man is it alright if I date Rose?" In the moment I "was" talking to a new girl so I said yes. Until a feeling of possession started to creep. It was small at first but every passing day it had grew and grew. I feel so fucking jealous whenever he's around me now. A week after they got together I decided to talk to him about how I felt because we were always brothers. I told him how jealous and how hurt I felt and all he said was "Yeah bro I used to feel like that too". That's it. Like as if he knew what that felt like. I was with that girl for almost a year and yes they technically "dated" but some whole ordeal of "not getting messages" caused them to break up but they didn't even last a month. And yet he just rubbed it off as something casual. It hurt a lot to hear him be so careless. The guy I thought was my best friend turned out to be a douche. I'm not saying I'm perfect whatsoever it just hurts. On top of that him and my freinds hangout almost every day. My mom even considers them family. I don't want to lose my friends but I don't want to keep pretending I'm okay. My family treats me like a maid with no respect. I try my hardest to be a good person but just to be spat on. My mom treats my friends like their God himself. Jax especially. He's her favorite of the three. Nowadays I just try to avoid him. I don't tell him about plans me and the other guys are doing. And whenever he is here I fake my mood to not cause drama but it's so God damn draining having to pretend. I just want to be a good guy but I don't want to suffer anymore. I even cut myself how much this hurts. I feel so alone even though people surround me. I even tried killing myself but later reconsidered it. I just need some help in any way.