Should I forgive someone that was a fake person for years?

Anonymous
We've been in the relationship for 6 years now. My boyfriend's sister has been a fake person the whole entire time. She even once pretended to reconcile with me, only for that speech to be fake too. I had unfriended her because I can't stand fake people.

All of the sudden, ever since she recovered from a stomach surgery, then tested positive back in Aug, she wants a truce. She wants to start all over and has send me a request. I haven't declined it but haven't accepted it yet. Others have confirmed she's changing and doesn't want anything in exchange this time, that all she cares is knowing we're happy in our relationship and are safe.

Should I forgive her and try giving her this chance? Do you think it's possible a fake person that gossips and pretended to like you for so long can change to a better person? Is that even possible?
Updates:
11 d
I never wished her bad nor anything. I don't even wish that on my enemy. I just still have my doubts. She didn't fake a whole friendship with me for a day, months but for the entire time we were dating. Then her previous apology from 2016 was fake too.
I want to believe she changed for the better but how do I know this?
Should I forgive someone that was a fake person for years?
1
1
Add Opinion