Hi Ronnid, welcome to the forum.
I thought I had it under control until my husband left me.
If you had it under control, then nothing has really changed in that regard. The change, obviously, is that you are now suffering what is very normal after a separation. I wouldn't get off track and begin trying to treat the symptoms, as you said, you had it under control and managed. Its uncommon that someone doesn't have fallout after separation, so what you are enduring sounds all perfectly normal, other than that its obviously heightened due to existing PTSD.
I would seriously just focus on the very normal stressors that is separation, get some counselling, you have online support here and other websites... and symptoms should dissipate by themselves again, as the only new trigger if you like, is marriage breakdown.
People to often get all caught up in the symptoms, when you know the cause... its more you just have to accept the symptoms as a normal result, don't fight with them and make it worse. It takes everyone time after divorce to resettle their lives, to readjust... all very normal. Its often a person can worsen the already worse situation, by compounding the issues, knowingly or not, ie. abuse cycle. You start beating yourself up, it compounds and turns into a nasty internal cycle which makes symptoms out of control.