Is it classed as hacking if someone gives you their password (on instagram)?

[RespectedWorlock826]

Someone, on instagram, gave me the password to their account. I did not know her in person. They said I could go on it/use it. The owner of this account then did not post anything on that account for several weeks. I assumed it was inactive as I could not get a hold of the owner. As I was looking for a fresh start, with a new account, I changed the email and password to my own, and deleted my old account. I had followed all of my friends, and posted my pictures.

A few weeks later (last week) the original owner of the account started commenting on my photos, telling me that she would call the police and get me arrested, as it is supposedly a crime in her country. I did not respond to her, because she was threatening me and swearing and I didn't feel like that was the best way to handle this situation. She commented things like "you are such a c*** just give the account back, or kys".

When I didn't respond to her, she started commenting on my friends' pictures, saying things like "tell your f***ing friend to give the account back or she is going to die". My friends were surprised that she had gone to such extreme measures.

I blocked her account, and reported it, but she keeps ommenting on different accounts. It seems to me that she is making new accounts just to comment on my pictures.

She has continued threatening me, saying that I could be imprisoned for "hacking" her account. In my opinion, it is not hacking because she gave me the password, and she allowed me to have access to that account. I just wanted someone elses opinion.

(Please do not say "just give the account back" because I don't want to give in to her hate. I don't want her to think that she can threaten people and tell people to kys to get what she wants.)