You do sound a lot like many of us LBW's here...we become so wrapped up in our family that we forget ourself...then we rely on our spouse for happiness instead of having our own.
I found in my case just taking a few minutes each day (cause like you that is all I had)I would close my eyes and listen...to the birds, cars, wind in the trees...or I would watch...birds, trees, ants...anything that had life to it! I would just relax and take it in.
The other thing I did was when I did have time off...I planned either a road trip (cheap hotels and cheap food) or a day trip locally, and would have fun with my kids doing things as if we were on a real vacation!
Once...I did charge a cruise to my H's credit card...he never checked his statements...and me and the kids went on a cruise to Mexico for a week...I took advantage of the pottery class on board the ship and made several things to bring home...one I was particularly proud of and still display in my home.
I would plan a girls night out to a chick flick...happy hour...or dinner
I also would invite friends over for dinner and games...
All these things helped me find MY happiness...it was then that my H took notice...I no longer NEEDED him!