One of my ex-roommates was the son on the receiving end of his father's coming out. He told me that it was all so shocking and he didn't understand it all at the time. The coming-out also coincided with his parents getting divorced. To him, as a 16 year old, he didn't immediately understand the whole situation, because he always thought back to himself, his sisters and his mom and dad being together, having fun... He had always considered his mom and dad happy together and liking one-another, so it just didn't compute in his that his dad would suddenly not like her anymore or that he had somehow never liked her.
The short term shock led to anger and hatred, because he looked at his dad as having hurt his mom. Over the next few years though him and his dad got closer again. It was a slow and gradual process. His dad was really patient with him and his sisters.
Now he brings his girlfriend to gay bars, to hang out with his dad.