I know a young recently married couple. During the courtship, (if you can still call it that) the girl's parents switched to a far more fundamentalist group within Christianity. The boy is Hindu, but quite a liberal one.
(On a side note, mixed faith marriages are a whole new debate, but a necessary one, as they are becoming far more common)
So the young couple decided to appease both sets of parents, and have two weddings, a Hindu one, and a Christian one. The kids themselves were liberal and respecting enough to allow for this, despite objections from the bride's parents.
So when the wedding day arrives, the parents of bride boycott, and are a no-show at the Hindu wedding, but the Hindu parents, in support of their son, attend the Christian wedding. I got to attend one wedding that day.
Now, I really don't know how its all going to work out. I'm sure things won't be smooth, despite the sincere prayers from both sides.
So this is just an example, but one that is becoming far more common in our world, of the pain and confusion conversion can cause, and the originating process was proseleytizing.