balancing act

I am with my children 24 hours a day.  I go to bed with them and wake up with them.  I am available for them at all times.  I am not complaining.  I am just stating a fact.  I chose this.  It was my decision to parent this way.  My problem is that I have never been able to find a balance.  Steve and I are working on having fairly regular nights out together (meaning at least once a month at this point).  My problem comes with trying to find time for myself. 

The way it is now isn't working for me.  Right now, I just go, go, go until I can't go anymore.  When I start to get irritable and crack, I leave for the evening.  I hate doing things this way.  I usually spend one evening a week away.  I don't make plans with friends because I never know when I'm going to reach my limit and feel that I'm not allowed to go somewhere alone twice in the same week. 

I need to find something I can do on a regular basis, maybe an hour a day.  I need to find something that makes me feel fulfilled.  My goal is to get rid of the days when burn out sets in, when I feel like I just need to get away from this house and the people in it.  I need be even-tempered and not have times when I feel like I'm going to lose it if one more person needs to have their nose wiped or spills their lunch on the floor.