A.J.
The sleep issue is almost always food related. I learned this from my step aunt who has 12 kids. Before attempting cry it out, you should increase his eating significantly ALL DAY LONG for several days first. Even if he seems content, if he's waking up at night, he could eat much more. It will take a few days for his body to register the increased calories and sleep longer at night. My son needed super stuffing (which totally worked) or he would wake at night (if we slacked during the day) until he was over 2 1/2. This may solve the sleep issue if he's full enough to stay asleep. I learned this too late with my 1st daughter who was still waking twice a night at 12 months when I learned this, and sure enough after 3 days of increased eating, she never woke up again at night. My younger two got stuffed and slept thru by 3 months.
At two years, this is largely a habit, so in addition to increased eating, do not give in at night, and if I were you, I would discipline the fits during waking hours. Your only other choice is to live like this, because he's getting away with it. Yes, he's sad when you walk away, but he has to learn to control it. He's not too young. My kids went through that and in no uncertain terms it wasn't allowed. If you discipline a tantrum firmly after ONE warning when it very first begins, it will never escalate to the dangerous head banging and all that.
Separation may be the cause of the fit, but it's still a fit. No different than a fit for your saying no or whatever. He's two. Don't let him do this. He will be much more happy when he learns not to act that way. Good luck! I know it's hard. If you need specifics on how we disciplined this let me know.
