The smartest thing you said in your letter is that this relationship is a big mistake. You’re absolutely right. He is a controlling man who has systematically isolated you from your career and your friends. Love doesn’t require this kind of control. A good man doesn’t manipulate the woman he loves with threats, ultimatums and tears. A real man doesn’t get his family to pressure his girlfriend. This isn’t love. It’s emotional abuse.
His behavior is most likely not caused by OCD. Claiming that it is may be his way of refusing to take responsibility for his controlling and unreasonable behavior.
End this. End it as soon as you can as fast as you can. Don’t give him this much power over you. If doesn’t matter what his family says to you. Their words are only words. If you think you are in danger, see if there is a woman’s shelter or services for abused women near you where you can get some help.
I wish you well.