People that succeed in having a "good" work/life balance may look at things from a day to day perspective, like blocking out twenty minutes or an hour a day for personal time. The day to day perspective isn't applicable to everyone. For example, take college students (the ones that spend more time at the computer lab an they do their own apartments), or new parents - there isn't really enough consistency
My personal strategy has been to take the down time when I can, because I don't know how long it will be until my next breather. I think there are some aspects of childhood that per-program an expectation of that daily "me" time (nap time, recess, Rugrats at 8:00 every school night before bed). And as a result, I was disappointed when I didn't have some free time every day. But sometimes, that simply isn't possible.
I have tried to change my frame of reference and look at the bigger picture. It's tougher to get disappointed when I expect some "me" time every week or every month instead of every day. I like to have Friday and Saturday nights to do whatever, and then begin the cycle of late nights in the lab on Sunday.
I've talked about this a fair amount with people who have "been there and done that", and I've received advice to zoom out even more - take the perspective that college is for planting the seeds, and once I get a job that college has prepared me for, I can begin eating the fruits of my labor; I shouldn't expect any "me" time in college.
Admittedly, that was difficult to wrap my head around. There is too much entitlement ingrained in me to be able to fully adopt that point of view - though sometimes it feels like I have.
I wrote all this and I just realized that I do take some time to myself during the week; I spend it at the gym. It's not everyday, and sometimes it gets derailed by other obligations, so that's where it helps to adjust my expectations. I always liked the expression, "Take it one day at a time", but I think my approach is a direct contradiction to that. Nevertheless, I'm holding out for the day when I can, as the Eagles said, take it easy.