assistance please

My wife and I have been married for 14 years and have 3 small children under 8yrs. of age. I am 39, she is 37. Our marriage is very strong outside the bedroom as we share many of the same likes and dislikes. She is an at-home Mother. Our problems lie in the bedroom. I feel as though my wife has no sexual attraction to me, even though I keep myself in very good shape physically. She insists that her sexual desire is simply not as strong as mine. In our 18 years together, I cannot recall an instance when SHE initiated sex. It seems as though she is going through the motions during sex just because she knows that I want to have sex. There are times when she will loosen up and respond positively, but typically after having a few drinks...which is seldom. Lately i have found that when I am out of town traveling she is using a vibrator that I purchased for her a few years ago. This has me completely unraveled as it is a very strong indication to me that she wants sex, but is not willing or able to come to me for it. My wife is by far one of the most attractive women that I know and I am incredibly attracted to her and try to tell her as often as I can how attractive she is and how she makes me feel. She does not seem the type that would run off and have an affair, but lately I am questioning this as we see it happen all the time in today's society. Please help me understand where to go or how to deal with my concerns.

thank you...

Ett gammalt kinesiskt ordspråk säger: Mannen är eld och kvinnan är vatten. Mannens eld får kvinnans vatten att koka. Mäns sexlust kan tändas omedelbart genom att de ser en vacker kvinna, medan kvinnor kan uppleva fantastiskt, men vara beroende av en skicklig älskare för att njuta maximalt. Acceptera därför att du får ta initiativet. Var lika uppvaktande mot henne som en nyförälskad man, värm upp henne med ett långt förspel och försök ge henne ljuvliga orgasmer. Då har hon ingen anledning att vara otrogen. Ett vanligt samlag, där mannen tillfredsställer sig själv med kvinnans kropp, kan kännas meningslöst för en kvinna.