If she has experienced abuse, this is definitely a factor. I'd wait for actual mental health professionals to chime in, but abuse has a long reaction and lots of consequences. With this info, I think you should probably try therapy and counseling, and I will decide NAH because this isn't about you. It's about her experiences and she's in survival mode. Sure, maybe the jokes take it a little too far (it could be a coping mechanism) but as someone who has gone through abuse, in various ways, you bet your ass I'm telling my partner that I would absolutely take measures to maintain my safety. This is something you need to approach gently, and kindly, with your wife. Work with her on it.