My colleague, who is lovely in most respects, has a history of fibbing. She does it a lot and as we've worked together for a number of years I've noted many occasions when a story she tells about her family, a relationship or a holiday clearly turns out to be untrue. I really don't want to think she'd make up something like this but the contradictions in what she says with regard to her treatment and its side effects are becoming increasingly extreme - bordering on outlandish - and I'm wondering if it is a lie that's become so difficult to pull back from that she actually wants to be caught out. Not sure whether I'm being unreasonable in thinking that she could be lying. Or what, if anything, I would do if she were.