You need to state some clear boundaries. You should NOT Be sleeping with her!
Come on this woman is on a dating site! Have more respect for yourself!
She is saying it's over and wants a divorce, she is on a dating site. You should no way be engaging her by sleeping with her
I may not be a 100% expert here but if you do not make some boundaries this woman will continue to walk all over you. Then she will not see you as a man. You need to be desired. Be mysterious.
Go out with friends, get a life, laugh, have fun.
Don't always be available for her calls or texts (unless it is pertaining to the children)