Now It's Time For Them...if I Have The Strength

I need to devote my life to being a mom to my three children. I find that I'm selfish and self-absorbed. I'm divorced and just broke up with my boyfriend. I loved his two children. I wanted to be a mom to them as much as they wanted me to. I felt at peace and like a real mom and content with a family life. Now that is gone and I know i need to carry on that feeling with my children even though it sincerely feels as if half of my family is missing.
I'm in mourning and my children don't deserve this. They've had a hard enough time as it is.