If she is compassionate and willing to support you I think you should explain to her what you are dealing with and ask for her understanding and compassion while you seek more therapy. I am married and I was just FINALLY diagnosed with C-PTSD and really struggle with my marriage to an amazing , but not perfect, man. He is supportive and understanding but can only support me to a certain degree as it is my responsibility to get professional help and learn how to begin recovery. I don't believe you have to be single to work on your C-PTSD and think it could even be better to have an understanding person by your side as you get better.