I'd definitely start by discussing it w/ her - you don't say specifically what you both have talked about yet. I"m assuming that 7 yrs of dating means that you do have excellent communication together. But there are a couple things to explore. First make sure that she sees the issue in the same light that you do -- i.e. she's not feeling pressure because your'e a horny guy and she isn't as horny. But I do agree that if the sex part of your relationship has fizzled out, its critical to deal w/ it because that should be an integral component of a successful & happy marriage (IMO anyway).
The easy part to deal w/ is the physical stuff - does she discuss this w/ her doc? Are her natural T-levels low? Thyroid or anythign else that might make her less sensitive, less interested, less whatever? I would personally punch my doc in the neck if he told me - yea you're getting older, it starts to go down hill here and you're pretty much just a cold lump of humanity in a few yrs -- at age 34?? Fuck that man. I was banging a 23 yr old when I was 34. I don't think there is a lot of truely understood knowledge about hormones, particularly in women and how it is all interconnected w/ our feelings, moods, etc. so I would seriously ask for a second opinion or some sort of more productive discussion or just look on the internet for some better info than that.
I will say that I think women do go thru periods of time where they don't want to be touched or have sex for whatever reason. How long those phases last I don't know but I do know they exist. I've experienced it. But not for months on end.
IMO its just plain wrong to not get a real good handle on the physical part just to make sure there isn't something fundamental that is affecting her sex drive. I'd even ask the OB/GYN if her t-levels are low, the viability of using a topical test cream like androgel or something. I'm suggesting this mostly just to illustrate the fact that peopel do this all the time- there are lots of women I've seen post on this forum and others that they use androgel or some sort of test support at very low doses. But also she is not near menopause yet so I don't want to imply that that is "the answer". Further I'm not suggesting that you attempt to self-diagnose & self-medicate w/ somethign either.
A random thought I wanted to include here - I personally experienced a bit of a hormone change at age 37 where I noticed things like I don't get nearly as much acne as I did my whole life. That was probably the most apparent difference. I'm not infertile yet, haven't hit anythign remotely like menopause and I certainly can't say I'm not interested in sex - hell, if anythign, probably more than ever. But I will also say I'm much more confident and comfortable in myself & my sexuality than maybe I was when I was 30 -- so there are lots of factors involved. But I just wanted to call bullshit on the age thing -- but also include that there are hormonal changes coming in the next few years that she should be aware of but I think its a copout on the doc's part to just say - yep, you may be sort of ok now, but you're screwed in a few yrs.
Then along w/ eliminating any physical issues, I'm w/ Rupe as well - do you think there are any communication issues between you? Is she self-conscious about the sex thing or tells you she's not interested or tries to sidestep the issue? Is she willing to discuss it? I'd realy dig into this if it bugs you this much - but I want to make sure that it is something that she is in the right frame of mind to discuss and that she doesnt' take it as an "attack" or a big frustration on your part that she is "doing" to you. If its as big a concern for her and she wants to pursue the solutioin & your communication is spot on - then dig into it. Might be a little frightening, maybe a little exposing on the part of her emotions -- but its such a fundamental part of a loving relationship its worth the effort.
Good luck!
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