Eight Days a Week, That Might Be Enough

The other day, I posted my Facebook status as: "Sometimes I wonder if I expect too much of myself or I'm just not pushing myself hard enough... tonight I didn't do 70% of what I set out to do & I'm exhausted!"  It was just the way I was feeling at the time (and many times before and after that moment), but I've been thinking about it ever since.  Which is it?

See, I'm out of shape, so I really want to exercise and lose some weight.  I also really enjoy writing this little blog and would like to spend more time on it.  Those two things don't sound like too much to take on, maybe an hour a day for each?  But here's the thing: I have a full-time job that enables us to do things like eat and pay the mortgage and other slightly important stuff.  So that takes up my time (including time for showering, dressing, commuting, etc) from 7 in the morning until 5 at night.  My lunch hour is actually only half an hour and half the time I don't take one anyway.  I'm married and have three step-kids, although they're only with us a few days a week.  The kids, I mean.  Hubby has agreed to live with me full-time.  Anyway, I still have to prepare meals (and yes, he helps) and clean house and do laundry and go to the grocery store and get the oil changed and... you get the idea.  So trying to find an hour a day to exercise and an hour a day to blog doesn't sound so simple anymore.  I should also mention that I require at least seven hours of sleep, my body and brain do not function with less.

What's the answer?  How do you handle this problem in your own life?  I'm looking for advice!