You have two choices.....

You either sit at home and think about the pit ticket you couldn't use

Or

You buy a £10 seat, jump on a plane and enjoy the final night of the show from a normal seat.

I know you're disappointed about not benig able to use the ticket, but surely you cannot expect your friend to give their ticket up for you to use?

They're presumably looking forward to the show as much as you are/were. Just because they've been before doesn't mean they enjoy it any less. I'm not being harsh, just a realist.

You will have other chances of pit tickets. You need to forget about it on this occasion.

You say you couldn't come last time due to lack of funds. I assume you have overcome that now? You have the money for flight and hotel? If you do, then jump on a plane, grab a cheap show ticket and enjoy the final night of the tour, safe in the knowledge that pit tickets will come round again.

I know you're disappointed, but I also know that if it was a choice between sitting at home and crying over an unused pit ticket, or sitting at the o2 watching the final night from a cheaper seat, I would go with the latter any day of the week.

Good luck with whatever you decide.