It means you have enough of that person. You can also say "I'm sick and tired of him". Examples: I've had it with all these problems he's causing every time! I've had it with all those crazy football fanatics! I've had it with being treated as an punchbag by him! I've had it with being cheated on by him over and over! I've had it with all these bills I've to pay every month!

It means "I'm done with him!" The person thinks they are 'fed-up" or tired of this person and has had enough and wants nothing to do with him anymore. You can use it alot actually. "I think i've had it with this stupid school!" "I've had it with you!"