How do you give up

Soo... my ex the love of my life recently broke up with me and said that he cheated and lied the whole time but I just don’t believe him that is not like him to cheat and tell me it to my face.. I’m use to him saying things to hurt me but I’m just wondering if he really loved me or not. We broke up about a million times and always got back together. I’ve always forgiven him no matter what he do or say because I love him with my whole heart but I’m tired of it. When we’re together he just seems so in love with me he’s a different person but then he just breaks up with me or say something he knows would hurt me.. I’m just soo tired of feeling this pain💔 but how do you let go of someone you love.