Advice for FTM returning to Work?

Monday is the day I've been dreading. I am going back to work and I don't know how I am going to feel about it. I feel like I am leaving my baby and not being a good mom. My LO will be cared for at a home daycare. I feel even worse because while I work 9-6, I commute to the city so my 9 hour day becomes an 11-12 hour day. I plan on pumping at work and feel that this might help. I'm just looking for some advice and some motivation so that I don't fall back into a funk like I did during my first month post partum.