Fiance has low drive with me but was more ually active with previous boyfriends?

My fiance has had a low drive with me for the last 3 or 4 months. She always marks when she has on a calendar, and the other day I stumbled upon some old calendars from her previous boyfriends. I saw all the marks of with them, and wow...there is no comparison. We have once a week on a good week...mostly once every two weeks. With her previous boyfriends, she was having sex many times a week. I have never asked about her past, but then I see this and it's staring me in the face. I told her about it, and all she says is that we have a much stronger emotional connection, and we don't need to have sex as often. I told her I disagreed. She also said she had sex that many times with previous boyfriends because she felt she had to just to keep them. So, if she was willing to give herself more often to them just to keep them...why wouldn't she give herself more often to me because she claims this is the best relationship she has ever had. I'm not asking for sex everyday, and I'm not trying to compare myself to the others....I just want to know what more I could do, because she is giving me very little help.