TW for panic attacks and just general angst - stay safe <3
he has the 'I could've done something to prevent it, therefore it's my fault' mentality for almost everything bad that has happened throughout their adventures
he's only now just starting to realise that he's not to blame for absolutely all of it (he's been told that it's not his fault countless times by practically every companion he has)
they despise feeling helpless or being told they can't do anything to help people
had a panic attack when UNIT was told by the UN not to 'interfere' with the construction of a British nuclear testing facility even though it was highly unstable
15 minutes later he went back in time and prevented its approval, of course
tends to go non-verbal during panic attacks (you can tell he's reached the tipping point when he stops trying to talk his way out of a situation)
Donna prompted him to start learning ASL to help them communicate when he has panic attacks
they start having little ASL conversations during boring UNIT meetings that she drags him to (they bicker like siblings)
he tries to avoid sleeping as much as possible since he has really vivid nightmares, usually about his past companions
on really bad nights he sneaks into the TARDIS and flies to a random nebula to watch the stars
sometimes they lose track of time staring at the sky for hours until Donna has to send the other doctor to find him
on those nights, the two doctors tend to sit together in silence for a while, heads resting against each other in quiet reassurance
he dissociates a lot more than his previous versions
sometimes multiple times in a conversation, especially if it's a conversation about things he'd rather forget
his friends have gotten real good at bringing him back (most of them have years of practice at this point) but River Song was always the best at it
which makes it hurt all the more when he finally feels someone tapping gently at his shoulder or calling his name and he looks around to see where his wife is
only to remember that she's not here
he doesn't cry very often - he's more likely to scream or kick something or go into problem solving mode then he is to cry
but occasionally, despite their best efforts to keep moving forward, keep running, they think about all the people that they've lost, all the lives they've ruined, all the companions they couldn't save and they can't stop the tears from flowing
...
he's so very old now
he's so very tired