well for me bitcoin is not a bad idea when you're retired after all.so better save your money for the future.i continue the bitcoin because there's a chance that migth bitcoin can grow more than spent my retirement money for vacation.
The comparison you make is bad - you are talking about investing your retirement money in bitcoin rather than spending your retirement money on vacation. The problem is - you shouldn't be spending your retirement money on a vacation in any case. Personally, I would be comfortable only with investing a small amount of my retirement fund in Bitcoin.
A portion of the retirement money is not bad in using for investment already so if @Godexists is going to use all of his money for investment, he surely is taking a great risks. For me, retirement money is supposed to be for relaxation after long years of working and, supporting yourself and family in expenses. We all have a choice and we can do whatever we want with the money but using all of it for investing right away might be bold move and rush decision.
Try to consider having a vacation for a while, it will be worth it especially because the money comes from your own hardwork. Do not invest all especially if you are not that familiar with cryptos.