"invalidated feelings" makes sense. It sounds like somebody like somebody else, but his feelings were not returned. When you have feelings for someone, and he doesn't have feelings for you, then your feelings are invalidated.

這是語法錯誤，This is not correct grammar. invalidate is a verb, feeling is a noun. You can, however, say "invalidate a feeling". That is grammatically correct. But it doesn't make much sense. You could also say "invalid feeling". still, I don't understand what that means. feelings are neither valid nor invalid..... are they? maybe... 這兩個說法語法正確，但是意思不太清楚， invalid跟feeling不太合適。 can you use it in a sentence?