Hey, Duet,
Same thing happened to me....it was a little sick, considering all of the absolutely horrible things I had gone through with my XABF...and we only knew each other 7 years, not 25! But those thought patterns were deep within me, like a set of ruts that are carved into a roadbed.
You have had a long time to get used to the patterns and habits that go along with being with him. They're ingrained in you, percolated down into your brain. When you think about that, it's never surprising to feel a little lost when you break that set of habits -- even a horrible habit like an abusive addict! -- and try a new way of living that might be better.
For me, while I was in it, my relationship was like my container, and I was like a liquid. Without the painful shell holding me in place, controlling my feelings, I felt like I was spilling all over the place for a while.
Maybe you just need to give it some time, and concentrate hard on rebuilding a better life for you and your family, getting back the relaxation and the joy in life that addiction tried to take from you. Old habitual thoughts are stubborn and hang on for a long time....and anyway, it's not like you want him to just disappear from the face of the earth. He's another human being, with whom you have some history, and I think it's normal to wonder if he's okay.
Love,
GL