Nowadays, “martyr” is usually used in the sarcastic sense — someone who is putting on a wonderful act of suffering in order to get sympathy.

“Don’t be a martyr” means don’t act like you’re being tortured and killed when your problem is really a very small one.

A martyr in history is someone who suffers for some idea of for some people so that they don’t have to suffer. Why? Because they love that ideal or they love those people. And as a side result, they may get famous or get respect. Today, lots of people throw that word around a lot. For example, let’s say Mom is making family breakfast of eggs on toast. And she accidentally burns 2 pieces of toast and breaks the yolk of an egg. So she gives her husband and kids the good toast and the good eggs and she takes the burnt toast and egg with the broken yolk for herself, because she wants her family to be happy. That would sort of be a martyr–especially if she doesn’t say anything to them about her sacrifice. BUT then if she mopes around the kitchen saying “Oh, poor me, I have to eat this crummy breakfast just so that you can enjoy something better,” then her husband won’t really think it’s so great. And he’ll say, “Oh, you’re such a martyr.” It’s like saying, “Stop feeling sorry for yourself. You could have just made more toast or given me the broken egg or had a bowl of cereal.” I don’t know what you’re doing to make your dad call you a martyr. Do you do something that you think people should honor and respect you for, but they don’t, and then you say “Oh, poor me. My life is so hard. I have to do so much” but really your life is pretty good and you have plenty of good stuff and shouldn’t really complain. Then he can say, “Oh, don’t be such a martyr.”

RE:
What does it mean when someone says you're a martyr?

A martyr is someone who chooses to suffer in silence and blames other people for not being more sensitive or attuned to their wants and needs.

It’s a victim. When someone is killed for no real reason they

are referred to as a martyr. It can be used as sarcasm.

Example: “Quit being such a martyr!”