@pluckyPenny923 I admire you for wanting to be there for him. I hope you understand that his pushing you away isn't personal. It can be incredibly hard for someone with PTSD to talk about their experiences. With being a guy, there comes a stigma with it because guys are supposed to be tough and strong. To show a weaker side it's hard. He may worry about burdening you with what he's gone through. If it's something recent it may just take time for him to be comfortable coming to you. But please believe me when I say it isn't you. Trauma changes people. It makes you fearful and you sometimes can't explain your thoughts and emotions. It's something that is so hard to heal from.
Be patient. There may come a time when he does want to talk to you but it isn't something you can force. Just let him know that you're there for him.
Do little things for you and your stress. It helps having a calm safe place, especially for him but also for you too. So self care for yourself is also incredibly important. Try to just be yourself. Which is hard I'm sure because you might feel like you're walking on eggshells all the time.
Try to educate yourself. There are many wonderful websites with information that can help you help him.
I hope that things get better for you both.