Abbey...hang in there. 25 years is a long time and the roots are deeper than he realizes. I can't promise that it will all work out and be ok again. But this isn't a car crash where in a split second you'll never have another chance to talk to him again. This will take time. And while that sounds terrible when you want nothing more than to make it all right again right this instant...it's a great thing because it gives you both time to process, grow, reflect, and experiment.
My belief is that separation can seem like a good idea in our minds because we can't logically weigh out how our emotions will react. It's easy to assign to much meaning to a recurring irritation, longing, feeling of neglect, etc. What's not as easy to see is that 1) that feeling may come from inside of you and not the M and you won't learn that until you leave, and 2) you may discount that 90% of your good feelings about purpose and identity and content come from a partnership you took for granted.
So trust in the roots, grow, read and post often, and open your self up to change. And when things get really tough post here and read stories. I'm a stranger but I am here for you and we are all going to make it through!
Me:38 XW:38 T:11 years M:8 years Kids: S14, D11, D7 BD/Move out day: 6/17/14, D final Dec 15