People, calm down!
Everyone probably knows that there are sometimes arguments in the family when building; that is probably unavoidable. However, it should be much rarer that grandpa buys the wrong windows.
Just post some pictures so we can get an idea. Is it about the interior or the exterior?
It is difficult when you have a concrete idea of something and then it turns out completely different. At first, it is extremely hard to get used to. In many cases, however, time will heal the wounds and maybe someday you’ll even find it quite good!
So basically, keep your head up and as was written, maybe something can still be saved with little effort (covering or something).
Best regards