What's that movie where a doctor lady allows a guy to live in a room in her house, and he then traps her?

Question

he's like this psycho that tricks her ex- husband to kill himself by pretending the gun has no bullets and saying that there' this game you place where you put the gun to your head and pull the trigger.

Then he traps the lady he lives with and makes the walls soundproof, and forces her to cut her hair and have dinner with him.

She tries sending a message to the gardener on a book cover written with an eye-liner, but the deranged psycho sees it first.

Eventually she infects him with something she was researching and runs away or something.

What's it called?

Answer 1

I saw a movie like that called "Deadbolt" with Justine Bateman.

Answer 2

Is it Pacific Heights?