Coly, I have no real help to offer you at this stage, though I will re-echo the advice about protecting your finances. Better safe than sorry.
I would add that by sending that text or any other aggressive behaviour will not help YOU. You need to be a steady rock. This does not mean approving his actions but moreso not adding to his turmoil. His life is not great at the moment and it has nothing to do with you (as in it isn't your fault/doing). Don't let him associate you with his undoing. Stay out of it. With the exception of protecting yourself and your D financially/legaly.
Best wishes
R 25 years M 14 years S11 & S13 Working on it alone since Oct 2014 M in trouble a lot earlier (~2 years) Feb 2016. 1st R chat in a yr. Next R chat Aug'17 Still together