Answer:
Hamlet begins by getting angry when Ophelia returns various love-tokens to him.
Step-by-step explanation:
After railing at her (’get thee to a nunnery’) he then, perhaps, has a sense that Polonius has put Ophelia up to this, asking ‘Where is your father?’.
After this he condemns her father as a ‘fool’, rails against marriage, and against women generally (‘you jog, you amble and you lisp’).
He then leaves, their relationship fatally damaged and when her father emerges from his hiding place he has no care for her welfare: ‘You need not tell us what Lord Hamlet said; / We heard it all’.
After this there is a brief final meeting with Hamlet in the pivotal scene (3..2), which is laced with sexual innuendo and then the next time we see her (4.5) she has gone mad with grief, following the death of her father.