Does sex change from lust to love overtime?

So... I'm a guy and I think I'm in love with my best friend. But it's strange... I dont want her sexually... I mean I think she's straight gorgeous and she has amazing, ya know, womanly features hahaha it's not that I dont think shes hot, but I dont think about sex with her... at all. I see attractive girls all the time and they can drive you crazy theyre so hot haha but my feelings for this girl are totally different. I think it's love... I mean we have fun all the time when were with each other and we make each other laugh and were not afraid to yell and get mad at each other and then apologize and all that jazz. So my question is... does sex go from like lustful to love? It's kind of a hard question to phrase I dont think i've explained it quite right but whatever. Basically the context of the question is that I want her in a... love context rather than just sexually. Does this make sense? what do you think?