Not sure where you got the idea that friendship doesn't exclude sex. Sex is only part of purely sexual relationships, and of more complete romantic relationships.
Friendship are called "platonic" because they're inherently non-sexual. The foolish notion of "friends with benefits" is a modern misunderstanding of friendship and boundaries in social relationships.
@Sun Squad
As for as the OP goes, yes, there's no need to have sex with anyone if you don't want to. If you're sexually attracted to someone but don't want to have sex with them, just ignore the sexual attraction, and it will go away eventually. That's what I do with virtually any attractive heterosexual guy, so I can be realistic and also interact as normally as possible with them.
You don't need to sexualise everything, or act upon every whim your body us.