How not to treat your friend on her birthday

I have known my friend Julie for about five years since the time we got chatting at the gym. I had always been under the impression she was six months older than me and I was therefore concerned to learn she would be spending her birthday working and had nothing at all planned to mark her birthday. This was after all a significant birthday and it didn’t seem right that anyone should do absolutely nothing on it so I suggested she came out last night for a drink with me and Reidski.

I got her a card – not a nasty in your face ‘You are 50!’ type card but a nice tasteful one for me to write my own message in. I wrote ‘Happy (50th!!) Birthday (surely some mistake)’. My brackets – and most unfortunately - my horrendously embarrassing mistake too.

Julie is not, as it swiftly transpired, six months older than me – au contraire.

Will she ever forgive me I wonder?