To find time for me isn't too hard, tbh. I can normally get stretches in the day if I want nowadays (kids are 5, 7, and 9) and in the evenings, its pretty easy for me to go out with friends, or I guess alone if I needed that. I've never done that but it occurs to me its a great idea. Also, my kids are now at an age when they have some activities they are all in together, or else the younger two are and the oldest is never a problem as he'll always sit and read and I don't know he's there.
What I find harder is finding time with my partner alone, not at the end of the day when we are both pretty tired. We've finally gotten round that by working out some drop in activities that will take all three of them for long enough for us to nip off and have a coffee, but its taken a degree of cunning and c-ordination.