Oral sex help

When my boyfriend goes downtown he’s usually down there for a long ass time because I can’t get off. It is frustrating to the both of us because he thinks he’s not doing a good job and with me it’s why can’t I reach euphoria. It has always been like this when he does it and it is to the point now where he doesn’t have a desire to do it anymore. He said sex is the last thing on his mind in this relationship, and I love him for that, but damn... it shouldn’t be like that?... I honor how he feels, but I’m just a lil sadden by it. He even mention an open relationship on my end if that makes me happy? I was hurt. Help?