I added some btc to Bitfinex but then I heard that it was hacked recently.
Is this exchange still trusted? What are your thoughts?
bitfines is as trusted as any other exchange is trusted and the fact that they got hacked, or even they got hacked and came back doesn't give them any more or less trust than others.
as long as the exchanges are centralized, without license and have no way of guaranteeing you your money they are all unsafe and can run away at any moment.