This is why I can't bring myself to use a flat iron. So far, I trim my hair in the salon by using a blow dryer only.
Weird, but I prefer a hot comb, heated on a gas stove and a thin paper towel (wet and dry) to test every time I put in on my hair, detangled with a very small toothed comb, small sections with one pass. If I can find a device to record the temperature of the comb before I apply it to my hair I'd buy that too. BTW, this is all talk, but that's how I'd do it...
The coarser the strand the more your hair can revert. Fine hair ladies who don't need a lot of heat to straighten, really don't need a hard press or need to use high temperature.
I'm sorry to hear about this. I'd try ApHogee hard core protein treatments every 6 weeks and in between light proteins in your DC for a while (months) in addition to a no heat regimen (work it out some how). I believe Nexxus Emergence is different from a protein treatment (I'll have to find the thread where we discussed this.)