Quote Originally Posted by Seraph View Post
Could собираться also be used for 'to brace oneself' or 'to steel oneself' ? Or is that quite different?
Not the verb собираться/собраться by itself, AFAIK, but you can use the idiom собираться/собраться с силами (or с духом) with the meaning "to summon one's strength; to muster up the nerve":

Ей пришлось долго собираться с силами/духом, чтобы признаться родителям в том, что она лесбиянка. (She had to steel herself for a long time, in order to admit to her parents that she's a lesbian.)

I'm not sure if there's a connotative difference between с силами and с духом in this case, though I would guess that с силами is used when you want to clearly emphasize physical strength.

P.S. Also, another expression with собираться/собраться с + instrumental: Он собирается с мыслями, "he's collecting his thoughts".