Idk what to do

Me and my boyfriend broke up he was heartbroken and he literally wrote a essay to tell me and I started to cry and I didn’t know why he said he loved me and I hurt him but it wasn’t meant like that after so I had heard he was having sex with another female and I’m very petty imma do u like u did me so I had this friend who really liked me we had been speaking to each other for like 2 years so that’s when to get back at my bf I had sex with him and then felt like a whore and planned not to do it again and he’s hurting I’m hurting and I want him back but I don’t know what to do I lost his trust can someone tell me what I should do or say ?? I really miss him and I was very careless 🤦🏾‍♀️😩😓