I'm in a similar situation in that I'm about to attend a wedding of an old colleague. She's lovely and I'm really looking forward to it. She has also asked for cash contributions rather than presents which is totally fair enough.
But I was going to send £50 and I'm now worried this is stingy in light of the other thread.
This isn't a wind-up btw, I'd really appreciate any thoughts on what the correct amount is for this type of thing.