Hey don't worry! Try reinstalling FH. It would be a shame if you left. I also had such a message when I opened FH. I clicked "more information" and then "run anyway". If you have Windows 10, it would look like this. Don't give up!
It's sad to see you leave over something like this. You are such a recognizable figure around here. Whenever you're having issues, don't feel alone! We are always open to help and figure out solutions. That's why our Help boards are there~ However, if this is what you wish to do, then I respect your decision. If you ever feel like coming back, we'll all be waiting! Be safe out there and take care~