Found this thread and just read it all the way through. As much as I'm sad there are so many of us, it's good to know I'm not alone!
I've been married to DH 12 years, together 14, 2 DCs 10 and 5. If I'm honest with myself, I think I married him on the re-bound from a very passionate but ultimately destructive relationship that left me very bruised. When DH came along he was reliable, trustworthy, totally transparent, kind and completely in love with me. This was such a breath of fresh air I convinced myself marrying him was the right thing to do, plus I wanted kids and knew he'd make a great dad.
Eleven years on and he is still that man and I was right about him being a great dad. We are best friends and rarely fight and have a lovely home together. But I do not have any romantic feelings towards him at all. He still goes to kiss me and touch me each day and it's as much as I can do not to flinch. Even though he would have it most nights if I agree, we only have sex once every couple of months to keep the peace.
As we have both always worked and I have quite an active social life (without DH), I have managed to avoid spending large amounts of time with him and I really thought I could go on like this because of the kids and in order to keep our lifestyle. But things have come to a head this year. Both of us lost our jobs at the end of last year and so were both at home together full-time for three months before I found another job. Having him around constantly has been awful - every little thing he does irritates the hell out of me - the way he walks so heavily everywhere, his hair, the way he smells, how very boring everything that come out of his mouth is. It made me think about what things will be like when we retire and this would be my life, which fills me with horror.
And secondly (and I completely realise how awful I'm being and that he doesn't deserve this), I met another man earlier in the year with whom I had such powerful sexual chemistry (and I'm ashamed to say we acted on it twice but have since agreed to put a stop to it, and stuck to it) that it's made me realise what I was missing all those years. It has also made me sad that I won't ever feel that with anyone that I can actually be with.
It's left me feeling not just unhappy but suffering from a constant feeling of anxiety. I go from deciding to leave (which would totally destroy him) to thinking 'this is just long-term marriage, you made the vows, try harder and suck it up'.