if you need to leave the home to "GAL",
it's ok to leave the kids behind,
you're allowed personal time, in fact it's a requirement for a healthy life, being a strong individual is part of being in a healthy relationship, don't forget the part of life that is just about you, no one else gets to live YOUR life, make it a good one.

- but hey don't feel like you can't be with your kids,
take them with you, plan something where its just you and the kids, leave the wife home alone every now & then.

Seriously it's ok, you're allowed.