Disrespect

I was told that if you let people disrespect you, you give them power over you. How do you change that? How do you stand up fir yourself when they verbally strike-out in frustration. You know they are not frustrated with you, but a situation. Still the sting of the strike does not hurt any less. 

Sometimes I think I am just making excuses for them, because the truth hurts. But, I want to change because I am tired of hurting.