Nothing obvious about your Dad's mental state in your post or in the behaviour you describe.
Entrapment is not applicable.
See an attorney in your area immediately to determine how you might be able to proceed forward
I did not wade through your long narrative, and address only your main question posed.
No, you have no grounds to sue.
What you should do is report the incident to police IMMEDIATELY--that should have been your FIRST instinct.
If your husband is wealthy, you are too. You will NOT have to go pro se. Immediately stop listening to his bluffing and his childish attempts to control and scare you. Immediately retain a family law attorney and let that attorney carry the load for you do you can care for your child. Best of luck to you.