I'm retired but when I was working I found time to play hockey in an adult league and I found time to work in my darkroom.
You have to allow yourself time for yourself. Mothers may find it more difficult when the kids are pre-school but everyone should be able to find an hour a day for themselves somehow to do some exercises and indulge in some kind of hobby.
Even if you write only 20 minutes a day, one day you will have written a novel. Really... I did.