I wanna propose to her but im not sure.

My girlfriend is perfect for me in everyway except for one little thing. We both go about sex in very different ways. Im used to just kissing and making out and that will eventually lead to sex but she doesnt like to make out not even kiss with tongue. She will just straight up ask "wanna have sex" and its just not hot at all. This is the first time ive been with someone who doesnt make out. Theres no passion no emotion at this point its like a business transaction and because its taking the fun out of sex for me i feel like this is the reason we arent having sex for a long time. Shes my best friend and imagine us having a future together but this issue has been makin me think twice. Am I over reacting? Or is there no hope? I dont wanna ve doomed to a sexless relationship before we even get engaged but i love her and i dont wanna leave her. I havent talked to her about this yet because a part of me is scared of losing her but i will bring it up eventually. Your thoughts and advice will be greatly appreciated.