Having orgasms but never satisfied.

So this has been happening for a very long time.
I struggle to have an orgasm through sex and I'm fine with that because I still enjoy sex, so I masturbate between for an orgasm.
I have the orgasm, very clear build up and stop, but that's all it is. A stop. There's no release, I find I'm not at all satisfied and can end up masturbating for hours and eventually just giving up because it seems like there's no end. So I am having the orgasm however I still feel like I need to have an orgasm, if that makes any sense?
It's very frustrating and I don't understand. Tried googling it but apparently no one has ever mentioned this problem before.
Anyone have any insights?