Depends on the situation. Some children have picked up some bad behavior patterns that were left unchecked by parents, where others could have something more serious going on that needs investigated further. You might start with your pediatrician?
That is a tough question... If it were me, I would be praying for direction.. But I am in early 40's and met a man who I have just moved closer to and we are connecting well also. And I am still praying for direction...
Do you feel threatened? Do you feel you are in danger? You have your child to protect. You could see counsel. There are lawyers who listen to a case to see if they will take it. There are counselors who can help also. Either avenue would be good if you need immediate help.
It sounds like you want to reconnect with your past. I would not recommend connecting again with your ex-husband. That doesn't bode well for your current marriage and it sounds like you are happy, but just feel like something is missing. Maybe you could try reconnecting with some of the old friends you lost? There has been time since your divorce, so it might be possible that whatever feelings caused them to distance themselves from you have had time to heal and it might be possible to move forward with those friends again.
So sorry to hear about your loss of your mother. Loss of family is never easy.