You are lucky to realize this. Most of us get here and do not realize this.
So I can tell you from personal experience that you completely face this fear. Live alone for awhile. Get to happy alone.
That doesn't not mean stop being a parent. It just means when it is not your parenting time, you do things by yourself. That does not mean all the time either. Go out with friends, meet and interact with others.
When you come out the other other side, you will be content.
"What is best for my kids is best for me" Amor Fati Link to quotes: https://www.divorcebusting.com/forums/ubbthreads.php?ubb=showflat&Number=2879712