What to do if being threatened by a law firm employee and coming forth with information concerning her firms client?

I got a text from my ex girlfriend who is a receptionist at a law firm. The text states "a new article came out after your threat to speak to Andrew's Attny.... You better hope I don't EVER find out have any sort of involvement in anything. You're nothing and no one in this. Remember that." I have information about her law firm's client that may be damaging to their case or helpful for the other side (defense). 3 days prior I had mentioned in passing over a phone conversation that I might call the defense lawyer and met him know of this information I have concerning the plaintiff. The plaintiff is this employees best friend and some of the info I have is from the employee (due to talking about the case). Some of the info is from personal accounts with the plaintiff (sueing for stress and depression, when I have proof of plaintiff being out at strip clubs drinking because I was with her) Is this a direct threat to not come forward with pertinent information involving this case?