Speaking as someone who doesn't 'get' the whole sex thing but can have romantic relationships with women, I am very aware of this. I do watch myself very carefully and maintain boundaries for the prottection of all concerned. Lacking any awareness of how to flirt helps!
Nevertheless. I've seen a few relationships inmy time where a man and a woman have made great play of being 'best friends'. They are supportive of each other, ccmmunicate regularly and help each other throuhg the inevitavle collapse of fomatic/sexual relationships. They are, of course, very much in love, but if you suggest to either one that this is the case, you get a wistful spiel about 'not wanting to spoil our friendship'.
Love is a high-risk endeavour, and these couples depended on each other to the extent that they couldn't bear to run the risk of losing each other in the fall-out of a failed romance. Sad.