I'M SO EFFN PISSED!!!

Ok first please excuse if I ramble, I'm pissed off and I'm really tired as I can't sleep.

So I have 2 kids my daughter is from my first relationship and my son whom is 12 is from a separate relationship of 12 yrs ago. My son's sperm donor had his rights terminated by a court of law for domestic abuse and other things. He has since married and has other kids with this woman. We don't know or have ever met any of them, other than their names I know nothing and him and I haven't spoken since even though he stalks us and has tried. We have run into each other as we live in the same area but I ignore them and keep it moving. My son doesn't know him and says he doesn't care to at this point in his life and of course my daughter is not his.

Anyways, so yesterday i was going through my 14 yr old daughter's phone for my random checks(which she no longer has access to at this point). I ran across an app for texting so I went through it to see what she's been talking about and with who.

Well going through it I notice two names that aren't "friends" I recognise ... Well that's because one of them was a female name he was using as a disguise to attempt to talk to her and then his wife had the nerve to include herself using another name.

As I'm reading his wife, that has never met my daughter goes full brain dead and starts telling my daughter she wants to take her shopping for clothes, bond with her, that she misses her etc.

I've blocked these people from everything i know as he has done this before but never his wife, now I guess she has joined in also. They just keep finding a way to go around all my blocks I've told them to leave us alone and they say "no, we don't have to" and laugh at me.

I'm beyond livid. The authorities said they can't do anything to stop this.

What makes him think he can talk to a child that isn't his and go against my wishes and then his dumb ass wife try to build a relationship with a child she's never met a day in her life.

I hope I made sense, I just need advice on what you would do.