Dangerous ex possibly contacting me? please help?

[kommando]

I have one ex, and he is nuts. The relationship was volatile, he was extremely abusive & due to possessiveness would imprison me in a cupboard in his basement. I fell hard for my current fiance and left my ex for him. My ex got a new girlfriend and started harassing her on social networks using fake profiles claiming to be me, he even called me threatening me to leave his gf alone. The girl found out it was him and he left me alone after that. Or so I thought.
He would call and make threats to come hurt/kill me using my current address, then it stopped after a while.

On Facebook there is a guy who persistently contacts me, speaking as if we've known each other for a while. I have no idea who it is, but just by his style of writing and prying questions I feel he may be my ex. After investigating his profile I cant tell if it's a real or fake profile. My ex (who previously had blocked me) is friends with this person, he tags him in statuses/videos, claims they train together and things of that sort, but it all seems fake and suspicious.

Its been 3 years since we broke up, im engaged with an infant and I'd hate to think my "baggage" would come back and hurt my family.Do you think my ex is possibly trying to keep tabs or is planning something?
In regards to interests, this guy has all the same interests and I just feel some of the phrases he uses are similar to those of my ex.

[Crystal]

call the cops
block his number
Fuuuck him and this third balll

[lalala:D]

Umm this is simple. One word.. POLICE

[boo]

Purchase a firearm that you can carry on you. Get a taser. Get pepper spray. Learn self defense.

[Anna]

Have you called the police on this dude?!?! Threating to kill you is major! But about the suspicious stranger, if you don't recognize the name, the. You should probably back away. Beware of this dude and take surious cation around him. Does he do the stuff you ex does? Does he like the same things or post things like you ex would? Ask yourself questions about how well you really know him and use some of info to help your investigations. But till then, I wouldn't talk to the dude or your ex. Ignore him and block him. You shouldn't put anything on Facebook/twitter/snachat/ect. That he could use to hurt you or find you. If things get to extreme, go stay at a friend's/relative's house somewhere he doesn't know about. Be very careful! I'll pray for you! Stay safe
- Anna

[Jake]

Get some guns sleep with one next to your bed and get a concealed carry license and always carry a gun on you also contact the police but just because you have contacted them don't think your safe because you really aren't this could just make him more mad

[Babs]

If someone is harassing you on FB then keep all the things they say to you and bring it to the police. Then you need to block the FB user and make sure you make your FB profile PRIVATE. Make sure there aren't any phone numbers they could get a hold of or addresses. Make all of your posts private so that ONLY people on your friend list can see them. That way if any of your ex's friends or any fake profiles are created, they still won't be able to see things on your page because it will be private. I would suggest making your pictures private as well. If the FB profile that is messaging you is friends with your ex, then I would guess your ex has his hands in this. It might be a fake profile or he might be getting a friend to do his dirty work for him, Since you have a baby and he has threatened your life before, it is better to be safe than sorry. Change your number if you have to, and make sure you are careful. Any texts, phone calls, messages on the internet - keep them if you can and if it gets to the point where you are fearing for your safety, bring what you have to the police. So they know what's going on and let you Fiance know so that he can help you through this.