If he texts (or emails) you with positive messages, respond more quickly and pleasantly. If he is texting separation talk, or being corse or hateful, do not respond for awhile. Don't say anything about it just simply let him stew for awhile. It's much harder to argue by yourself. Start to positively reenforce that behavior that you want from him.
^^^^^this is excellent advice, Jefe. I totally agree.
Me: 30 H: 35 M: 5 years S2 Signs of MLC started Feb 2014 BD - PA July 2014 Piecing/reconciling late July 2014