
Going back to work was one of the hardest things I had to deal with after DS. For me, it was just one of those things where I had to just push through it and get it done one day at a time. Time does make it a little easier, as in the more you do it, the easier it gets. Once you get into a routine, it gets better. But even after 2.5 years, there are still days when it is very difficult to leave. Just one of the things you have to deal with as a working parent. Just keep reminding yourself why you are working, whether its the financial aspect, or the fulfillment you get from your career, or whatever.
I would say try to put it out of your mind as much as possible for now. You don't want to spend the rest of your maternity leave dreading the inevitable. Just enjoy the time you have left. And, when the time comes, your LO will be fine. I think they handle it much better than we do.