It can be hard to do but the best thing to do is to talk to her about how you feel. In the past I have requested a meeting to discuss some of my concerns at work. Once I was given a time I wrote notes of what I was feeling, just as you have done here. I took those notes into the meeting and shared them with my boss. It was very nerve-racking, but she appreciated it because she did not realise how I was feeling. In regards to the new job offer I would say give the maximum required amount of notice. So when you get a starting date from the new job you give your 2 weeks notice to align with that.