Hi. I would just like to know if you have heard of cases where people's money have been stolen from their wallet. If so how can you avoid this?
The only way to steal money is if they compromise the target machine/network. To avoid this you need to look into general security advice for computers and network. Read this thread:
Beware of Malware: Think Before Acting!. What you could do is:
1) Keep the majority of your coins on an offline machine and only boot it when you need to use them.
2) Split the coins across several different devices (e.g. desktop wallet, mobile wallets) and make sure to use 2FA and encryption where available.