Dead Sex Life

Hi everyone! So me (25) and my boyfriend (28) have been together for almost a year and a half now, and I am strugglingggg…. Our sex isn’t bad, however it isn’t really passionate, nor can we go multiple rounds. In the beginning of our relationship, I constantly was the one initiating the sex, and im at the point where it’s starting to make me feel pretty insecure because why doesn’t he want me the way I want him? I get we have different libidos, and im trying my best to work with him. But it’s so annoying laying there thinking about getting f**cked and having to ask my bf and get shot down. I don’t know what to do, I love him, I don’t want to breakup but I also am now finding myself thinking about looking elsewhere… (NOT CHEATING) but it feels stupid to do that simply based off of sex. Any thoughts?