You are completely justified in all you say. She needs to lose that job and all contact with the ex-boyfriend. And it's high time she makes these kids her number one priority. You are neither father nor mother, and way too much responsibility for these boys is being put on you, IMHO. You are the one least in need of therapy. She and those boys need some family therapy.

Lucky for everyone, you seem to have some clue about the leadership kids need. She should be so very grateful and following your lead on how to get these kids in hand, which it seems, at least, she is doing.