It was hard for me, for a long time, to know what brought me joy. I kind of forgot. It's especially hard, I find, when your children are very little, and you work, and you stay home, and you have so MUCH on your plate. I don't suppose my plate has less now, but it's different, and with the kids being a little older, I am able to disengage from things they can do on their own (like grabbing a snack, entertaining themselves, putting their own dishes in the dishwasher).
Now I have a lot that brings me joy. And man, I see it on my kids faces when we are laughing together, or doing something silly, or just enjoying a walk. It's not like those moments are all day long, but they are there, and I try to be more me with them as they get older. I sometimes realize I am a lot more fun around my 19 year old niece - she is like a friend, which is entirely appropriate. But she sees the person that I am more than my kids do - I am more a taskmaster with them, which, again, is entirely appropriate.
Anyway, it's nice to feel like I'm doing this part kind of right - enjoying stuff, having my own joy (with some guilt, but that is fading!), and enjoying time with them, too. WITH them.