"Keep a stiff upper lip"
Someone who has a stiff upper lip does not show their feelings when they are upset
"Keep your chin up"
to stay cheerful and hopeful during difficult times
"Take one for the team"
to agree to do something unpleasant that you do not really want to do, or not have something that you want, in order to help or be kind to other people in a group
"Grin and bear it"
to accept something bad without complaining
"Suck it up"
To put up with something; to deal with something, such as pain or misfortune, without complaining.
"Roll with the punches"
1] to cope with and survive adversity
2] to not allow difficulties or criticism to discourage you or affect you badly
"Nil illegitimi carborundum"
A humorous pseudo-Latin expression meant to translate as "don't let the bastards grind you down," meaning do not succumb to the oppressive influence of others.
[The Free Dictionary]
And a personal favorite, especially in the context of this question,
"Put on your big girl panties"
Pulling up your big girl panties is more than just moving on or dealing with that particular moment. It’s really about standing up, leaving the junk behind and moving forward. It’s about being strong and audacious and bold.