Student or Learner
can we say " don't die AFTER them." ? Does it make any sense?
Do you mean "because of"? I'd say "Don't die over it."
The meaning is that whatever you're talking about is not as important as the other person seems to think.
I'm not a teacher, but I write for a living. Please don't ask me about 2nd conditionals, but I'm a safe bet for what reads well in (American) English.
If I said "Don't die FOR them!", I might be talking to someone in the armed services, telling them that the people he/she is fighting for are not worth dying for.
Can you give us any context?
For example, I am trying to understand something to a group of people but they are not understanding it. Finally someone says to me that don't die after them ( don't waste your energy for them, they will not change their attitude).