Are these sentences OK?
She might hate you for that. (for doing something now)
She might have hated you for that. (for doing something in the past)
Don't you ever do something wrong?
It's not easy to find someone decent to get married.
We've done a lot of work, but we still have so much to do.
Do I have to do everything for you? / Must I do everything for you?

Question

Are these sentences OK?
She might hate you for that. (for doing something now)
She might have hated you for that. (for doing something in the past)
Don't you ever do something wrong?  
It's not easy to find someone decent to get married.
We've done a lot of work, but we still have so much to do.
Do I have to do everything for you? / Must I do everything for you?

Answer

The others are perfect.

Don't you ever do something wrong?  
I can imagine a native speaker saying this, but much more common would be "Don't you ever make mistakes?"

It's not easy to find someone decent to get married.
To get married needs a "to" at the end, but that probably wouldn't be as natural a way to say it as:
It's not easy to find someone decent to marry.

Answer

Don't you ever do "anything" wrong?
It's not easy to find someone decent to get married "to".

the rest are fine