Mismatch and marriage

I love my boyfriend and we are talking about marriage but I’m worried about getting engaged because we are mismatched in the bedroom. I want sex more often and I don’t have the “I want to jump his bones kind of feeling.” I think that I don’t want him “enough” sexually and that I’ll want other guys but that won’t be an option. I know it’s my thoughts (model below), but I’m worried to make the jump with these feelings/thoughts. I love him for a million other reasons though and don’t want to lose him either. How do I figure out is this a reason to leave or stay for the other reasons?
C- Marriage
T- I don’t want him enough or we are mismatched sexually
F- sad
A-avoid the conversation
R- we just stay dating and everything stays the same