I hate how people react with the "Oh you not a good Christian if you don't help me"

I hate it so much I am a type of person who gives people things who is a quiet person and is very kind to everyone I meey but I hate when people take advantage of me using me being Christian to emotionally black mail me. A classmate of mine who is in the same lectures as me told me to cover for her meaning lie to our professor because she was going out to vape with her friends and I said no I am not going to lie you go tell him. As she looked at me saying "oh I thought Christians are supposed to be loving and helpful I guess not saying no hate like Christian love" the feeling of hitting her right there was boiling it feels so draining saying so and people prseve you as a bad person