I liked e2 of s5 đ
Donna is hurting & reacting accordingly. If Harvey is showing that he does not care ("ripping the band-aid off") she is doing the same to him.
OR, she might have been expecting honesty from Harvey & to find something out after 12 years has come as a huge shock to her vulnerable self.
OR, she might be looking at this gesture as Harvey's attempt to pity her just like his love confession last season which was retracted & given a different twist.
Those are my thoughts & I am sure she will appreciate what Harvey has done for her sooner than later.
Following the season four finale, showrunner Korsh told THR that Donna leaving Harvey "could lay the foundation for them ultimately getting together, or it could lay the foundation for her ultimately moving on and getting with someone else."
"However, if she was really fully ready to move on, she wouldn't have gone to work for someone within the firm, she would have left," he said. "So subconsciously I don't think she's ready to move on and maybe she is hoping this gets Harvey to change his mind or see her in a certain way.