Can somebody wirellesly read my messages or facebook messages if I have jaibroken iPhone?

Can somebody wirellesly read my messages or facebook messages if I have jaibroken iPhone?

Yup. If they had physical access to your phone, they could have installed any number of apps to be able to read anything. If they have access to your icloud account (user/pass) they can also read everything you're doing.

With that said, if you have jailbroken it, and no ones been able to install something on it, the only way anyone would be able to read anything is if you installed a rogue app that gave that sort of access.