Welcome to forum! While I myself am a suffer I can empathize with you and applaud you for wanting to help by supporting your friend. I would suggest maybe having your friend visit here too if that is an option. If not, then I hope you can at least find what you seek to better equip yourself. Dealing with PTSD can be an emotional roller coaster, I would also suggest giving your friend plenty of space when they seem to push you away. As a suffer like myself, I know that without a support network (even if it's one person) I at least need a person or people who can empathize with me and what I am dealing with. So again I say, Welcome to the forum!