仔细考虑某事,to think carefully about something, or to say something that you have been thinking about.

reflect on/upon someone/something

I think it would be better if we brought this meeting to a close, and you and I get together once you’ve had time to reflect upon the situation.

I don’t want to reflect on it.

I will reflect upon the offer.

So you might wanna reflect on what that kind of disappointment will mean for him.