Still struggling

Had two months no contact. Was truly delightful. I felt somewhat emotionally healthy again. Over time, he took up less and less real estate in my brain. Then he got through and contacted me last week. I have had a relapse. I was ok through the week...work keeps me busy, but have had two bad weekends in a row. Last night was classic gaslighting: him the rational, reasonable one who just wants to salvage a friendship (what salvage? we were never friends); me the raving, ranting, unstable lunatic. Can the aftermath of being someone's narcissistic supply for six+ years lead to temporary insanity when triggered? I was so angry, hurt, sad last night and I behaved so appallingly.