To answer your question, yes, it's possible to have a strong friendship, engage in sexual activities, and not have any romantic feelings. I have had a friend with benefits for over a year now and that describes our relationship perfectly. We are close, we have sex, but we just love each other as friends. Now, take this with a grain of salt, because it's often hard to do that. Usually at least one person develops romantic feelings, which seems to be where you are at and he isn't, so that's a rough position to be in.

If I were you I would just focus on the friendship. If he's as close as you say he is I think he will communicate with you if and when he feels he wants to pursue a romantic or sexual relationship with you. Regardless, he's not ready for anything right now, and the best thing to do is building your friendship. After all, that's why y'all stopped sexting and making out, so maybe that's what you should do.

Good luck, and feel free to PM me if you have any further questions.