“this”指代前面的“he wants”后面的内容,即他提出的要求“give up working and stay home to look after the children”,而”that“是引导”she feels“后面带的宾语从句,引导宾语从句只能用”that“不能用”this“,但是在指代“he wants”后面的内容时,可以用”that“,即整个句式可以改为She feels,however,that that is too much for her.这样的话”that“就重复了,故用”this“更好.