While it is just a broad statement as each and every persons' situation, living arrangements, schedules, etc. vary, I can only speak for how I approach this.
I am married. I have to work to pay bills because I haven't won the lottery (haven't played it either which probably helps). That prince from Saudi Arabia still hasn't gotten back to me with the money he owes me after I lent him some to make it to America. Jerk.
I look at my to-dos and chores and actively say to myself "these get moved to this time so that on this day and time, there is no excuse or reason for me not to be painting". For instance, I now mow my lawn on Thursdays after work. Laundry is done Thursdays as well. Need to iron shirts? Iron them while watching Nick Hankins. Grocery shopping is Friday after work. That means all day Saturday or Sunday, I have no real obligations but myself.
Essentially, bargain with yourself. You get paint time and the world gets their stuff when you give it to them.
If there is anything I learned after having a lot of really scary health problems (They found a tumor in my spine 2 days before I got married. I had a heart attack 6 months ago at the age of 40) is that we have, somehow, been programed to feel bad about "me time". We have all the time and energy to go to work and do the crappy stuff we need to do and just flop over when it's time to take care of the things we WANT to do. Bargain with the world. Give it what it wants when you want to give it. Make the most of your time cuz the world has a strange way of taking it from you.