loving a rape survivor

I'll try to keep a long story short. My girlfriend (23) and I (24) have been together for about a year. She suffers PTSD from a rape experience when she was 18. She suppressed her memories but they came back to her at the age of 21. I am aware of the struggles she is carrying and have the deepest understanding, also for her altered views of sexuality ever since. I know that she has had consensual sexual intercourse with several men after she remembered. Something she seems not to be able to engage in with me. We've been a little intimate with each other early on but the difficulties grew stronger and her desire felt. She still has flash backs sometimes so i understand her hesitation conserning sexual intimacy. I have never put pressure on her and never pushed her to anything she did not want. She says she feels comfortable with how I treat her and how I am understanding and sensitive. However intimacy of any kind has decreased drastically the past few month to almost none and I am suffering from it, since i feel undesired. It seems like a small issue but I am starting to suffer and worry a lot. She tells me that emotionally and also technically she likes intimacy with me but has brought up several reasons why she isn't able to engage in sex and kissing over time. I am perhaps unreasonably starting to doubt that and believe that I am the issue. I have terrible self doubts and dont want them to affect how i act.