It's very sad that I heard it, I hope you keep trying to be the best.
You must create your strong Email password and do not save private keys in online software.
You can save it in an offline place, such as hard drive and flashdisk.
It's a terrible shame for you, you always hear of hacks but it's only a reality when it happens to you! PLEASE get a hardware wallet if you decide to invest again, otherwise you're playing a game of risk.
Take note hodlers! Please keep your funds safe.