Well, we kind of knew that a pediatric sized valve was going to be a problem for the long term. But you've actually carried it well for a pretty good run.
You've lost a lot of weight, and that's a difficult and wonderful thing, and is surely helping with the valve situation. Hopefully, you can hold off for a while longer.
I think a problem is your cardio's use of the term "rejected," which isn't the process that's going on when a valve goes bad (except for human (homograft) valves). It's a poor description, likely intended to make it easier to explain (like saying blood thinner in place of anticoagulant). Use of these terms rings alarm bells here, even when the doctor turns out to be quite competent. It's just people trying to watch out for you.
Try to ease up on the stress, as that chews into your valve faster and more surely than any other, nonmedical thing, with weight coming a close second.
I hate to think of you having to go through this again. If and when you do, make sure your preacher takes a bath in Lysol and gargles with Listerine before he attends another pre-op barbeque.
My very best Christmas and New Year's wishes,