AFAIK, you cannot catch "shingles" from someone, but someone with a shingles rash may give you chicken pox, if you never had it.
As people said, its a resurgence of chicken pox you had as a kid, caused by a depressed immune system or big time stress (same thing, stress reduces your immunity)... chicken pox never leaves you, it goes to sleep...
and when it wakes up, it's a $%#$% of a thing to get. Can be super painful and leave nerve damage, so treat it yesterday and you'll be fine. I got an episode myself a few days after getting really really angry at someone who threatened my family, and coming close to blows... should have, I may have been in jail for a few days but that may have released the anger and avoided shingles ;-(
It's pretty amazing how getting pissed off or stress will impact your immunity! It opened my eyes to being more relaxed about things, I'll tell you that...