Speaking for myself I’ve only used the trainer three times since this started and only had to validate files after using the trainer my game has been booting fine since validating the files I have the steam version on windows 7 if that helps.
Do you have a scan exclusion in your security software for -> *.cheathappens.com?
Did you try and switched browsers? Disabled certain browser add-ons, ie ad-blocker or script blocker? Some browsers offer to block dangerous downloads or protect you from dangerous websites (Firefox, Chrome). Tried to disable this feature?
But why can i start the game with the trainer and everything works fine?
Because it is using a bypass to let the trainer work.