I really need help with jealousy. Any one that can help!?

I can’t stop overthinking about my friend and her soon-to-be boyfriend , I feel like I’m jealous but not of HER, I’m jealous of HIM, like, I’ve known her for so much longer , me and her have always been closer, and this guy comes in and is gonna take up a bunch of her time. Idk, ik I shouldn’t feel this way. She reassured me she would never leave me and I guess I’m also scared of that. I had a breakup with our friend oldest bsf a couple months ago , I guess that might’ve done more damage than I thought. I feel like I’m losing myself , and then I thought I found myself again once me, my bsf , and the guy became friends , but as soon as I found oit she liked him and he liked her its like everything crashed:/// I hate feeling this way but idk what to do

Okay so, this is gonna be very detailed because it's a lot. I have a friend that going to be in China for an exchange program and that's obviously amazing! But...I got super jealous because my biggest dream is to live in an Asian country but as I always do when I feel jealousy instead of letting it consume me I tell the person I'm jealous of so that I can ensure it doesn't feel odd carrying around jealousy that they know nothing about if that makes sense. And so I tell him and he brushes it off, but the jealousy stays with me. I've also been having some harm OCD thoughts beforehand so the two thoughts merged and I thought of horrendous thoughts it's so scary cause these thoughts are not just intrusive, they have a meaning attached to them😭. Back in the day I'd get jealous and it would be just that...no harmful thoughts towards the other person but just because I've been in an OCD rut I have actually been unable to feel negative emotions anymore without them having to be tainted with harmful thoughts towards others or myself honestly like wth😭! I hate this! What do y'all do with intense jealousy??

I just randomly had this thought when I was driving and I’m super anxious. A couple weeks back I was really jealous of my gf and her guy friends playing card games together in one of their classes and I wanted to see if she would get jealous if I was paying more attention to my friends in my class, two boys one girl. She was in the class and my teacher was explaining a card game to one of my friends who is a girl and I was trying to see what he was saying and showing her but I had to get closer to do that and in the back of my mind I think I was trying to make her jealous by being closer to another girl. I’m terrified because I would never flirt or do anything with another girl. That girl also has a boyfriend. I’m just stuck in my thoughts right now and don’t feel like moving or doing anything, I feel like throwing up. Someone please comment and help me