Im lost

Been with my boyfriend for a year now and he has REALLY REALLY BAD paranoia and trust issues to the point where he thinks im cheating ALL the time when im genuinely not. I have to prove to him 24/7 where i am, if i go to the supermarket more than twice a week he thinks im going there to cheat, he accused me of having sex with someone at the park just because i brought my child to the park with my friend and there kid. He had NEVER see any boy text or call my phone, i have been nothing but loyal to him and its just not good enough and no matter how many times i reassure him he just doesnt believe me. He says his past relationships didnt cheat so it cant be because of that. He always thinks im mumbling stuff under my breath when im not and i do think sometimes he hears voice to think im mumbling stuff when im not!? I went shopping today and its very hot here in london today and i wore sandals and i was walking up the stairs in the supermarket and my sandals make a loud noise walking up the stairs as the supermarket stairs are echo and make my sandal noise sound a little louder than they actually are and apparently that noise is me cheating and someone smacking my bum! Ridiculous and WILD i know !! He keeps saying if i keep cheating ( even tho im really not ) he said he will cheat back and its honestly so heart breaking to hear because then he will be cheating on me for literally no reason 😔💔 Im tired, drained, sad and depressed… he speaks so vile about me and my body.. calls me a sl*g and says im “loose” , majority of the time i am tight but if we have sex and im randomly ‘loose’ it means someone has “beat” my p*ssy… disgusting and vile! I love the boy to bloody pieces and i really dont want to let him go because hes honestly the perfect boyfriend in many other ways but his paranoia, trust issues and accusations are ruining us. We have sat down so many times and spoke about it and i keep telling him maybe he needs to see his doctor for some help but he wont accept it, hes so in denial about needing help. I always tell him hes being paranoid for NO REASON but he doesnt listen and still points fingers at me for cheating. My bed and sofa broke and he said thats because of me “cheating” , ive never cheated on the guy and i never would. Ive never cheated in my life! I just dont know what to do anymore, im so lost, i know i should leave him but i cant bring myself to do it because im so inlove with him… hes my best friend and boyfriend all in one! His paranoia, trust issues and accusations have got worser and worser over the past couple of months… just broken ☹️💔