From my point of view, he has two options.
a) He tell her to stay away, she blown her chance. He probably don't feel like it, if he has feelings for her. He will have no more drama with her though.
b) He responds to the email, and tells her if she wants to stay in his life, she needs to obey some rules.. Like he's not her marionet, if she attacks him once more it's all over and so. I think you catch my drift.
If he just responds to her email, without setting some basic rules it will just return to normal and he will get loads of drama.
- ILJ

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