Just checked...
Mass isn't unusual. They have to "serve" you in person. The only thing I can think of is maybe she went to the police and got a 24 temporary restraining order so as to buy 24 hrs of protection until the court opens monday morning and she can try to get something more permanent (alone with an order of temporary custody). So the cops call and say you are restrained temporarily from contacting and "harassing" your wife and kids. They probably should have said a time limit but they probably try to be as vague as possible to "protect" the supposed victim. This isn't a real documented restraining order but violate it and such will be used against you in court as proof of your abusive nature.
From what I read (see below) I don't think she should win a permanent restraining order. Here's some thoughts.
1. How will a MA court have jurisdiction? She's not a resident of MA. Your divorce was probably filed before her restraining order or any MA divorce case because you filed while she was still driving there so any hearing MIGHT be an opportunity for you to serve her with the Texas Divorce case and put the court on notice that they don't have jurisdiction on this matter of a Texas resident and kids ALREADY the subjects of litigation in Texas.
2. What proof of "abuse" does she have? A liars game but she needs proof of actual harm or imminent harm. Sending emails to her friends asking for prayers for your family it's "abuse".
3. She has to serve you. But you still may want to hire a MA attorney (or GO to MA to defend yourself) to appear on your behalf.....argue lack of jurisdiction....and put it on the record exactly what she's obviously trying to do....steal the kids away to MA. In that KY case I linked one of the biggest mistakes he made in hindsight was not going to the Texas restraining order hearing where the Plaintiff and her affair partner OM hired a "professional" psychologist or psychiatrist to tesitfy that the husband was abusive based on a couple recording of a mad dad who's kids were stolen from him and talking to the children. I'm sure the KY husband was told not to worry about the hearing under the same argument I gave above but he lost (one big difference in facts is that the wayward wife and kids had already lived in Texas for 8 months or so BEFORE filing the restraining order).
Here's a link to a handout sheet on restraining orders in MA:
MA Restraining Orders