ANSWER:
When they abuse you like this, they want to depress you or to get a negative response from you.
If you simply smile in their faces and whenever they abuse you, you say to them kind words, you would be like pouring water on a red hot piece of iron!
Never defend yourself when they accuse you and never engage with them in any kind of argument. Simply smile in their faces and say to them you are so nice and kind couple.
This would kill them softly as they are unable to get you angry. This way, you have the upper hand and they will be the ones who are wrong and disrespectful. You will be in command and would manipulate them as you wish by having the upper hand.