i didn't start to get ME time until DD was about 18 mo old, as she was such a constant nurser and such a momma's girl. and by the time DD was 18 months old, i had already been a mom for 3 1/2 yrs, as DS is 2 yrs older than DD.
but then i just had it, and was so mad at and jealous of DH's time, time to play soccer, time for soccer practice, time to drive alone w/o kids.
so we worked out a every other friday thing. and it is great. and then once he couldn't play soccer outside anymore, he said i could have every friday. i don't, b/c then i feel REALLY GUILTY, but i do try to get out every other friday to the local scrapbook store to work on the kids' photo journal scrapbooks.
and yes, the ME time is essential to a momma! so get it!!