Join the club, there are literally MILLIONS of us guys in your very same situation. You fell for the old "Bait and Switch" routine. You thought she was a high sexed person just like yourself, you were compatible. THEN SHE CHANGED and YOU DID NOT! It's weird, these women become new mothers and they adopt a whole new attitude on life that is COMPLETELY WRONG. The focus their lives on being mothers rather then lovers. This is the worst thing they could do for their children! They need to be lovers FIRST, and mothers second. I could find a half dozen experts in marriage that SAY JUST THIS. The best thing that mothers can do for their children is to be lovers with DAD, otherwise they risk being SINGLE mothers, and that is not good for anyone. I can tell you from my own experience that childbirth can REALLY screw up a women and her sex drive. It is VERY common. When my wife started having children, I was willing to give her a break on the sex thinking that childbirth and the pressure of being a new mom were TEMPORARILY causing her to not have much desire. Well, 8 years after the birth of our last child and me getting fixed to make me safe, she has less desire then EVER. Funny thing is that I now am no longer being patient and I am voicing my needs for affection and sex, and guess what, she tells me she thinks I am having a mid life crisis. I personally believe that the so called MLC is just the husband finally doing something about the sex life he so desparately has ALWAYS wanted.
Well, anyway, back to your situation. First step is to try and get her completely checked out, especially her hormones. 2, she may have developed a Hypoactive thyroid, childbirth can bring these on. Hypoactive thyroids basically slow her body down to much and will cause weight gain and a great dip in desire. I know, my wife has one. Step #3, you need to become the "World's Best Husband". This means, romance her, communicate with her, pick up as many house hold chors as possible, watch the children, spend lots of quality time with the wife, a bizzilion differnet things. I would recommend reading the 2 books by Beverly DeAngelis about "What Men want Women to know about Men" and "What Women want Men to know about Women". The first book is for you to read and see if this book describes your needs and if so, see if you can get your wife to read it as if it is an owners manual for you. The second book is to try and understand women better, and make yourself into a better guy.
I will warn you, that not much is ever going to change in your relationship until your WIFE does something about this, there is only so much you can do. That's what really bites about this situation, us HD guys have so little control over the most important aspects of our lives, our sexualities. After you read the first book above, you will completely understand how deep our sexualities impacts our lives, and how we are completely at the mercy of our spouses. We have so very few options other then divorce.
Good luck!
If you find something that works, PLEASE LET US ALL KNOW!!!!
