Its not what you don't say, its how you don't say it.

That's quite an accomplishment not to speak to someone you live with for that long.

Maybe she heard you talking to someone else and that conversation made her uncomfortable

Silence speaks louder than words, don't ya know?

Maybe she was referring to 'what you say' on the internet.

Maybe the silence is what makes her uncomfortable. Try to befriend your roommate since you'll be living with them for the semester.

Did she retreat to her safe space?

She can't kick you out if you're on the rental agreement but if she's harassing you, you can make a formal complaint to any tenancy branch that deals with renter agreement/dispute type issues and just explain to them she affects your daily enjoyment of the rental spca, and is attempting to bar you from the apartment which is illegal. She sounds like a head case.

I think that she's trying to say that the silence is deafening.

How can you not talk to your room mate? You two need to sit down and either work it out or come up with an exit strategy. Nobody wants live in silence, walking on eggshells.