I’m just so lost and I need so much help

Hello. There’s a lot to unpack with me. I’ve been feeling down for years now but it’s been ascending a lot over the past 2 years. I have issues with some family and I have terrible anxiety. Currently, I’m struggling with jealousy of an friend that my ex has. I feel so ashamed for it but I can’t help it. Everytime I think about them I feel a pit in my stomach and I automatically feel nauseous and emotional and that leads to me self harming. They both live in my head. It makes my heart race and it physically hurts me. If there’s any tips to help that out it would be highly appreciated. Next, I’m very insecure and I’m a bad overthinker. I get irritated easily and I constantly need reassurance with my closest friends. I get so anxious from some things with them sometimes and I feel a rush of emotions. I always feel like everyone is gonna leave me and secretly hates me. Then I have intrusive thoughts. They’re so terrible. I have these voices in my head that sound like me and help me overall operate. Those voices tell me bad things sometimes. It’s scary to think about some of the things that I think. There’s a lot more but I’ll cut it off here. Any help would be appreciated.