Thrown Back

A few years more than 10, ago. The world as I knew it was kicked out from under me. I had married very young and had a child. 13 years into the marriage, my ex lost it. He began beating on me and cheating. I divorced him and moved on with life.
That's the short and sweet version.
He did things I didn't believe him capable of, and I feared for my life. Seriously. To the point of leaving the kind of note that says "if I turn up dead or missing, it wasn't an accident or suicide" hidden in important papers. (He broke into the house and found that note, but I digress)
I had acute PTSD for a good year and a half after. And some how, I began to heal. I became stronger. Better.
About 5 years ago, the ex started again. texts. drunken calls. (Mind you, he's still with the youngen he was cheating with and now has additional child.) I was a little smarter this time and called the cops who paid him a nice visit. As the cops said I could have "wanted the texts/contact" and he hadn't physically hurt me (5 years ago) they wouldn't put a restraining offer on him. They said I could put a stalking order, but I didn't at the time. (I know, I know.) Anyway the visit from the cop quieted him down.
And then today. He drove by my house. (the one I've tried very hard to keep him from knowing about.) He stopped and talked to my son (21yrs) who was outside. He claims he was in the area for work. (In his private vehicle, not work truck) I don't buy it. He lives 45 minutes away and ends up driving by my house on an obscure side street, 6 towns away at the exact time that my kids outside. The kid he turned against me at 15 yrs. old, who came back into my life a year or so ago, after my psycho ex beat the crud out of him?
And when my son called to tell me... Instantly. instantly right back. Into the state of mind. Into the fear. Into the shaking. I can't do this again. I can't. I've slept with a baseball bat beside my bed since, and that's with out him knowing where I was. I don't feel safe. I've got nothing to prove anything. I hate being right back where I was 10 years ago. I hate that I am STILL afraid. That I know the hell that guy can visit. I hate that for all the healing and strength, I am thrown right back in. I feel hopeless that I'll ever be free of this cretin.
He contacted my son just after the holidays, after a year of non-contact. and within 3 weeks, he just happens to coincidentally drive by my house. Yeah. I must be stupid.