How can I change my IP address

I would like to know how to change or fake my own ISP assigned IP address (that anyway always changes from a pool after each login) The problem is that my ex husband is a hacker and might be able to email me and ***** me down. He is a very violent person and was beating me and our kids. Now I am in Germany and he disappeard and police look for him. He could be anywhere. I have changed all my emails but when I check the old emails I know he stills tries so hard to ***** me down. Are proxy server safe enough or could they be contacted and pass my covered-up IP on?