the whole day (long) 表示一段时间时前通常不加介词 for,例如:
Kathy and John were together the whole day long.(《英语惯用法大词典》第504页)
the whole way 相当于 all the way,其前通常是不加介词 for 的。如:
They had come the whole way from Khartoum to Croyton by air.
Surely it isn’t necessary for them to walk the whole way.
The little girl who sat next to me on the coach ate sweets the whole way.
但是,我觉得在 She was sad for the whole way home 这一句中,the whole way 前面也可以加 for(当然不加也完全可以),因为这里的 the whole way home 从表面来看,是指一段路程,但其实也可理解为一段时间(回家路上的这段时间),此句指的是 was sad 这个状态持续了整个回家路上这段时间。