I try to spend at least 15 minutes (sometimes an hour, if I'm lucky) for myself. This can be anything from reading a book, crocheting, treadmill time or just a hot shower. My husband and I try to have at least 2 hours a week, just us. He often travels to see his clients and I'll go along just so we can talk in the car and catch up.
I will say that when my boys were babies and young children, this was often very hard to accomplish, but worth working for. Now that my boys are teens (14 and 18), my me time and my honey time have grown exponentially, often in to several hours a day/week, again, if I'm lucky.
Just as a side note, you might want to consider thinking outside the box on what constitutes me or honey time. When my eldest was born, me time was my husband taking our baby grocery shopping so I could sleep in. When our second was born, me time was my husband staying home with both boys while I did the grocery shopping. Another example: when the boys were little, honey time was the children going to bed early on a Saturday night so we could have a quiet dinner at home just us. Sometimes we cooked up a meal together and ate by candlelight. Other times, we sat on the back patio, watched a storm blow through and ate pizza. Now that the boys are older, we leave them at home to clean house while we do the grocery shopping together. Sometimes this includes breakfast out or a Starbucks run; other times it's just shopping.
The point is, me time doesn't have to be an expensive day at the spa and a date night doesn't have to require a babysitter. What counts is that you and your honey commit the time to each other, in a way that works for your family at that point in time. Yes, writing it on the calendar takes away spontineity (sp?), but it does show commitment. You and your honey get to decide which of the two is more important to you!
Good luck!