Please sit down and talk w/ your boss

"This nonsense has to stop. I told you that yesterday. I will help you. I have real issues that need to be addressed. Why don't you work with me to address these issues? "

-- The above email from your boss is not too bad.
-- There is something you and him need work out, Email will not help in this kind of issue, you need sit down talk/work with him.
-- You need get a clar action plan (list what you need to do step 1,2,3) to get the issue addressed.
-- Regardless how you think you work hard, the most important thing is you need your team member deleiver the result you need as a team and make your boss say good about your team's performance.

Thanks!