I can certainly make sence of your explanation. I was single (divorced) and my kids were first too. Then when I found the right man, it was pretty amazing that my 4 kids and his 3 kids blended so well. I isn't like having to make a decision about who is the most important. I know that I am probably one of the blessed few, but I have a wonderful mate, and my kids love him too, they don't feel like they are now second place. His boys were not sure about having to share dad, but they soon realized that having a mom around was pretty sweet too.
Most of all, no matter your decision, be committed to it, make it a decision that will work for you. There are as many relationships as people, and when it's right, you'll be happy. Just make sure that the goals are in harmony, and no one has to sacrifice.