People lie for several reasons. Probably, the most popular reasons are, 1) they either did something they weren't supposed to, or didn't do something they were supposed to, and they don't want to face the consequences, get punished, or get broken up with by their girlfriend or boyfriend. 2) they may not want to hurt someone's feelings. 3) They may want people to think highly of them, so they make-up things about themselves to make them look good to others. 4) they may be embarrassed about things going on in their personal life and don't want anyone to know about them. Some people lie because they are sneaky or don't want certain people to know what they are doing. Then there are people who lie just to lie. I call these pathological liars. They may have grown up in a family that lied all the time because they may have had a lot of secrets. And, because of this, that's what they learned to do. It's normal or seems natural to them. I hope this helps.
They want you to retaliate it because it's a disrespectful way of saying I don't like you just to make you feel bad just like bullying so don't listen to them they're not lying at all their bullying you?