Ditto Judy!! Dump the guilt, it's toxic. (Yeah, right, I know. I think I spend half of my mental power trying to dump mum-guilt. If the mum-guilt wasn't there...I don't even want to THINK about how much more I could accomplish, and how much happier I'd be. Just by not tieing myself up in knots, and enjoying life and my son and all this rather crazy place has to offer.)
You know, probably the single most important thing I've noticed in spending time with kids...is that you have to WANT to. Even if you can only squeak in 10 minutes...if it's obvious that you WANT to be with them, are excited by them, enjoy their company...they blossom under that light. IMO it's better to tell a child "not right now, love...but in "x"minutes, or after 'y'." than to force yourself to spend time you don't have with them. Kids GET when they're wanted, or when you'd rather be elsewhere.
But as to your question:
Not as much as I used to!
If you don't count cleaning (we turn on music and dance while we clean...everything from Swing to Punk to The Devil Went Down to Georgia...I DESPISE cleaning, so I have to make it fun, in order for it to happen on a regular basis)...I USED to play with my son 5 or 6 hours a day.
One of the ironies about homeschooling is that we actually spend time thinking up ways and rearranging schedules to get our son away from US and around other people...playing with other kids, learning from or playing under the guidance other adults, etc. We spend so much time together, that our biggest fret is ensuring that he has at least an hour (most days) where "Mum! Champion of all that is right in the world (and whether or not I'm standing up straight)" isn't looking over his shoulder...so that he has time to learn who he is on his own. It's harder than you might think. Most kids are in school until four...and then their parents are trying to get a little time with them before dinner/bath/bedtime. So we mostly do it through sports/classes/camps. Sigh. I WISH some kids near his age would move into our neighborhood.
I'm with you though, on finding that balance. I'm WITH my son so much (and half of teaching is playing)...that I have to consciously remember to take off my teacher hat and climb trees without talking physics or biology, or build without talking engineering or architecture, or paint without talking science or history...It's HARD. When I can manage to do it, and just have silly time...it's sooooo worth it.
These days, with my teaching hat OFF...I typically manage half an hour to an hour of out and out silly time.