This sucks man. It is not your fault at the end of the day. There are always going to be scammers who try to steal - and do figure out ways to steal from people. It does not mean that it is your fault.
HOWEVER, it is your responsibility to keep them safe. There is a big difference. Knowing the environment of Bitcoin currently, you should be more careful with how you store them. Paper wallets are the best because there is no way for a 3rd party to infiltrate you, or no easy way anyways.