Just to be clear, I'm the sufferer rather than a carer. I've been married for 14 years and with my hubby for 18. In the beginning of our relationship, the trauma was still fairly fresh. It had occurred 5 years before we met. It was definitely a challenge. We are both health care professionals, but have no more training in psych than any other nurse or paramedic. He was wonderful and patient, and I did my best to communicate what I needed (not something I'm particularly good at). Somehow, we made it work.
Nearly 20 years later, I still deal with PTSD rearing its ugly head from time to time. The more obvious symptoms, flashbacks, nightmares, depression etc. are cyclic. I go for long stretches now without dealing with them at all, then I'll end up triggered somehow, and something will bring them back into my life for awhile.
What has remained, though, is the lack of a sex drive. Even when things are good, it doesn't seem to be "normal". It's not like I have flashbacks during sex (I HAVE, but not in a long time), or have any sort of trust issue with my husband. I don't have any good reason that I can explain. It just isn't there.
My husband has always had a similar viewpoint as ISH. He's loving and supportive, and would never want me to feel like I was in a position where I felt like I "had" to do anything. But at the same time, 18 years is a long time to be patient.