I'm on the other end of child rearing, as my daughter graduates high school this spring.
I completely panicked when I was home with my baby. Suddenly everyone identified me either by my role of wife or my role as mom. Freaked out. I'd been a career woman until then and it felt like I'd lost all of that.
When my girl was six months I returned to work, loved it and managed to keep a decent work/life balance (but in hindsight I didn't carve out enough time for me).
A few years later I started to feel like "career", "success" etc meant nothing. Especially in comparison to my daughter. And in comparison with living a full and complete life. I think one of the greatest gifts of motherhood (to me) was that it taught me this lesson.
Getting back to being me also became easier year by year as she grew older. For each year that passes they become less work and more fun (in my book). Soon you'll have a mini-me that you bring along for things that you enjoy (or enjoyed as a kid and couldn't do as an adult). For me it was theme parks (only then did I realize how much I'd missed them), international travel, hiking in mountains - all of these things were me, and so much more fun to share with my kid.
In addition I would carve out time for me to do things I did before I became a mom. When she was three I did a couple of sailing weekends. I did a university course when she was 4. Subsequently I got divorced and had a weekend per month all to myself.
I chose to eat healthy to stay slim, I often lounge in grungy clothes but also dress to the Ts pretty frequent. Exercise was mainly weightlifting baby / toddler, followed by chasing todler, then obstacle courses (play grounds), then various activities on holidays + gym.
Now 49 I feel more like myself than any other point in life. I had a bit of an "empty nest" panick two years ago, but got focused on what comes next - my girl now accuses me of looking forward to her moving out because of all my plans.
And without a doubt: my girl taught me to be the true me. She didn't subtract - she added.