So my fiancee and I have been together roughly 5 years.  We are getting married at the end of this year, which all of the plans are well in motion for.  That being said, our sex life has significantly dropped off, and I feel myself becoming less interested in her sexually and attracted to other women.  Let me be clear, I would never act on these feelings because I do love my fiancee, but I am beyond frustrated at this point.  I have talked to her about the fact that I am tired of being the constant initiator, and if I don't, then just nothing happens. And I mean months, not just a week or two.  She always apologizes and says she understands and she'll be better.  Which might lead to a handjob or sex once or twice over the course of the next couple of weeks, then just back to nothing.  It's not that she ever really turns me down, she just seems so uninterested when anything happens.  She swears that she loves having sex with me and reaches the finish line every time we are intimate, but her actions and body language says otherwise.  

On top of it, I feel our increasingly distant intimacy giving me feelings of insecurity that I have not felt with her before.  I hear her getting text messages or FB messages in the middle of the night, but she never addresses it the next day.  I know one of her friends especially messages her at weird hours a lot, so I don't think much of it, but the lack of intimacy is driving my brain to think things it never has before.  It seems silly to feel this way because I really do trust her, but I feel like my damn brain is all twisted up from all of this.

I just don't know what to do.  I love her and want to spend the rest of my life with her, but also don't want to have to essentially force myself on her or literally grab her hand and put it on my dick while we are laying in bed to get things going (which has literally happened).  I feel my eyes wandering and just becoming more and more detached from my relationship with her, which I never ever want to happen.  AITA for feeling this way?