This will do us both good

I think I have already know the answer of this problem. And my decision is to resign the job. Because I really felt very insecure of this colleague and I no longer trust her anymore. And because she is my friend so I think no point continue working with her because if i don't leave she will also find fault with me. And no point carry on this job even though the boss really treat me very well.

Because I know that if I leave the company, this will do us both good. And I have thought this problem for a long time before making this difficult decision. If it is others and not her.....I think I won't leave this job. So don't know this is a better decision but I think this is the best way.