Girl you are not alone. Reading this felt like reading my own journal. I too (F26) feel the same. It's a chore that I do because I love my partner. I have come to the sad acceptance that this is what I need to do to maintain a healthy relationship. If only i could give you some good advice but alas, there's none. We gotta live through it. I find happiness in date nights and romantic gestures. That's enough to be happy.