How to help my boyfriend with orgasm embarrassment

My boyfriend doesn't cum in front of me. He will only do it if he's masturbating alone. Whenever we have sex I can always tell when he's about to orgasm because I'll hear him try to contain his moan, he will turn bright red and stop. He doesn't even really like hand jobs or blow jobs because he doesn't like orgasming in front of me. He said he doesn't know why he just gets embarrassed. I was wondering if anyone had been through this. I want him to be comfortable with me and I want to be able to get him off