Be careful about taking on a S. S thrives on negative energy. The more you fight the more pleasure they get by weaving you deeper and deeper into their web of deceit. Do not think that they have not anticipated every counter move. They do this for a living because they have no other life. They get a thrill out of this. This is how they get their kicks.
All the advice that I keep getting is to drop the S and get clear. Hence the prerequisite to maintain boundaries so that you do not lose if the relationship turns out to be predatorial.