I'm a new member to this site and have a question that I'd like some other opinions for. I've been dating this girl for about 9 months now and things are pretty serious and moved quickly. We're in our mid 20s and obviously there are big decisions ahead for us. Before me she dated this guy for ~6 years. Two summers ago he moved away and came back with a new girlfriend after. My current gf and her ex broke up then got back together a short time later. He went away again this year and this time she got a new boyfriend while he was gone (me). Our relationship has been phenomenal ever since and she's been all a guy could ask for in just about every department - especially considering her history with this guy.
Which brings me to my question...
Our sex life started off pretty phenomenal which is to be expected when she hasn't had sex in 4 months. It stayed like that for a few months and then pretty much died completely. We're now having sex around once a week (me initiating 90% of the time) which is a lot less than I'm used to and I'm pretty confident it goes that way for her as well. We were close friends before dating and I know she was pretty sexual with her ex (she claims there sex was awful). I'm not sure what's going on, she's stressed with her job but I feel like it's kind of draining on our relationship and also my ego. It wouldn't surprise me if she had sex over Skype with her ex more than what she's having now with her actual boyfriend. I can say with pretty good confidence that I'm at the very least an average lay. She's slept with 5 people in her life, me 12 and I honestly got laid more when I was single then what I am now. I'm the farthest thing from a sex addict and it's not so much the fact that we're not intimate very much as it is that I feel like I'm doing something wrong. Whenever I bring it up she claims she's just not that sexual of a person but I don't buy that. I've seen the way she talked to her ex about that sort of thing and our relationship hasn't had that in a long time and she also slept with 4 different guys in the few months she was single last year (claiming she used them for sex) so I don't really buy the not that sexual aspect. I feel like I'm doing something wrong or that I'm inadequate in some way which has never really been the case in the past. I'm not a cocky person but I'm a decent looking and have had good reviews about my skills in the bedroom (and size) regularly in my past. I have a few thoughts...
-She isn't that sexual of a person and what I've heard/seen from her conversations in the past was based solely on the fact she hadn't gotten laid in months and was lonely.
-My sex appeal is just not there anymore. We started off with great chemistry between the sheets and now its died completely. I'm not sure what I can do to make her want me more if this is the case. Any ideas?
-Her stress levels with work and other responsibilities kill her sex drive, along with a lack of exercise.
-I'm not as good a lay or don't have the sex appeal as what she's had in the past.
Like I said I don't care about having sex once a week but I feel like that's pretty low for people our age without kids and it's just deflating to think about how she talked about the other guys in her life (before we were dating) that she's had sexual relationships with. I know that after a certain point people hit sexual ruts but it feels like this girl wants nothing to do with me sexually the vast majority of the time. She's the best gf in the world and a girl I can see myself spending the rest of the life with but this sex life, or lack thereof is pretty depressing right now.