I've been in a relationship with a guy for 2 years off and on. He's retired military and suffers from ptsd. Hes always been up front about his ptsd and I am always here for him and try to do what I can to help however sometimes he just shuts me out. I understand he needs time alone but he walks away from us for weeks at a time. We'll be great for a few months and out of the blue he doesnt want to be with me anymore, than about a month later he comes back. I always try to be understanding and be here for him and I do love him very much. I'm just at a loss. Do I keep trying or do I just walk away?