Just tell them you want to take a gap year, it really doesn't have to be complicated.
Your life does not need to be compared with other people. Not at all. Not even a little bit.
There's more than one path through life, and going straight through the education mill, for all it's ingrained into many people as being the be all and end all, I promise you it isn't.
As for your friends, if they judge you then they're not really your friends, and people who aren't really your friends don't really matter at all. If they don't judge you then it's a non-issue anyway.