Why is divorce so hard?

I know I'm not in love with him anymore. We were together 13 years and 7 years married. We have 3 gorgeous boys. I am just extremely heartbroken that I broke our family up. He is still madly in love with me and has now realized how emotional abusive and controlling he was to me. He says he's changed and sometimes I see it and other times I don't see a change. He didn't want the divorce and he still asks for another chance. I've gave it to him multiple times but it still doesn't work. So we're continuing with the divorce. I'm so scared he's all I've ever known. We've been together since we were 14 years old. Got pregnant at 15 and overcame so many obsticles over the years including losing a baby a few years ago. I'm so afraid of being lonely. He was my best friend and still is but I just don't see him like my husband. I don't want his touch etc.  we're putting up the house for sale and moving closer to family. I hate that the kids have to start a new school. I'm not sure why I'm making this post. I guess to vent. But does this get easier? Is it normal to feel heartbroken? Lonely? 
We did try marriage counseling but it didn't work for us. I had to much pain and I am now seeing my own counselor to help.