Hi Jade, welcome aboard and glad you decided to say hi. I know exactly what your saying, and it took some time for my wife to actually come around in this instance also. Basically, the only way for a partner to truly come around is to have them learn with you. They must know what you know about PTSD, and they must understand that this is not something that is just out there, or in our minds, because its real, and its a killer.
Once spouses often know the true issues surrounding PTSD, why our brains have chemically imbalanced and so forth, they can then often support us in more substantially positive ways, than just negativity. It takes time, it truly does, and is certainly a two way street in regard to relationships. Both must learn and know their specific areas in order for a relationship with PTSD to work effectively with little extra relationship stress caused.