我会很难过.
I'm going to be very sad.
例句
我一个人在这里已经很累了,请不要质疑我,那样我会很难过的。
I am alone here already very tired, please don't question me, that makes me very sad.
如果你受到伤害,我会很难过的。
I shall be distressed if harm came to you.
I will be sad.
I will be very sad/I shall be very upset