Are you unhappy with your current situation? Do your accomplishments make you happy and satisfied? If you are, you may not need to change, you just may need to accept yourself for who you are.
We all need a balance between work and personal life, but that balance can be different for different people. I spent a long time berating myself for constantly checking blackberry at home, for volunteering for projects that I knew would take a lot of time, and for simply thinking about work while at the dinner table with my kids. One day my husband finally convinced me that it is OK to be who I am. I love my family dearly, but I would not feel fulfilled as a person if I did not have a challenging and rewarding career. That is just who I am. And it works for me and my family.
I'm not saying you are the same way. If you are unhappy, I suggest setting some real boundaries on yourself (do not touch the blackberry until children are in bed, commit to being home by X time X many times per week, etc.). But I urge you to consider whether it is change you need, or if it is acceptance.