Sex? HELP

My husband and I love each other but why am I not obsessed with Sex like other people. I can go without sex for weeks and when people talk about it with so much excitement, I feel anxious because I am like what is with these people... I understand when you get an orgasm it feels great BUT I don't feel anything when the D is actually inside and that's what's sex actually Is!!! so the act of intercourse doesn't turn me on much...

is that even "normal".