My ex husbands wife is reading my emails on my son's phone. Is this legal?

I recently found out that my ex husbands wife has been reading my emails from my sons phone. Is this legal? She has also been using my social security number to check Texas' State Benefits Department (Food Stamps, Welfare, Medicaid)and see if I am receiving benefits. Is any of this legal and what can I do about it? She has also had a neighbor spying on me, submitted several false reports to CPS, and spent the last two years spreading hateful stuff about me through text email and facebook. She also gave my social security number to a third party individual. What should I do?