The forgetfulness and problems managing his time sounds a bit like ADHD. You may want to visit this site for some info: http://www.additudemag.com/
Even so, your complaints about him make you sound more like his mother than his lover. You can't monitor him like that and set yourself up for disappointment over and over again, and not feel the stress.
Why did you choose to have him move in with you so soon? I think you may want to ask him to move out and work on his shit, and maybe take a break from this relationship until you see some genuine effort on his part to grow up and get the help he needs for whatever he's got going on, whether it is ADHD or some other psychological issues. And it may very well be that you two are not as compatible as you once thought, and that it is time to let go and move on. You have to do what's best for you - if he goes into a "tailspin" that is on him, not you! I wish you well.