Ugh. This is my least favorite form of the last-panel twist, the Unexpected I'm Sorry. (Yes, I just made that up, but you know what I mean, right?) There's never a surprise; he'll either man up or wimp out.
I predict he will man up (wimping out seems pretty much out of the question), and one of two things will happen tomorrow:
1. Brent will say, in effect, "I'm sorry but you're no longer invited to our wedding."
2. Brent will say, in effect, "I'm sorry I'm not the man you had in mind for your daughter, but I love her with all my heart, and she loves me, and as a mother isn't that all you've ever really wanted?"
My money is on #2. I'd like to see #1. I'd love to see something original.