Mommy Dearest, extreme tantrums, and complete brakedowns

My son is an extreme toddler, not the living life on the edge, getting into everything, live for the moment type. The hour or more meltdown, the out of control scary, screaming, breaking toys, laughing and biting type of extreme toddler with PDD-NOS. I am easily overwhelmed.  I often feel beaten by his extremes and frustrated. I am tonight, like most nights, at the end of my little rope. Partly because I have been at this so long with so little progress or insight on how to change things, so I am tired. And, Partly because I feel all alone. Not from family and loved ones, even though there is a disconnect there sometimes ( I wouldn't get it if I didn't live with either.) but from anyone that is qualified to help us. When my son was (finally) diagnosed, the first thought that went thru my mind was "now we can get help, you can help us!" .  I was optimistic, now we can get a handle on this and make it better. But as time has gone by, and we have started school and PPT meetings, I am finding out that I am alone. It takes monumental effort just to get a foot in the door, then you need to prove you qualify. And sense my son is only PDD-NOS, he is mild and extremely high functioning when you look at him right. So we never qualify, we are pushed back to square one, move back two spaces.  

As I said, I am tired, I will admit this to anyone that asks, I need help. So help me. I don't know what to do anymore about his extreme behavior. I dread public places, and more recently, even family get togethers. He knows every button to push and I turn into Joan Crawford from Mommy Dearest, crazy, screaming, insane (Just sans the heavy drinking). I through my own massive tantrum and melt down, it's totally inappropriate, it's childish, but its what I have resorted to.  I know of all the "techniques" I have spent way too much on any type of "behavior" parenting book. These things make sense to me, but I can not get them to work. Like I said, I need help.

And now, my son has fallen asleep tonight after crying for about an hour. He went completely nuts (a nightly occurrence) and had to be dragged out of my sisters house (laughing) after throwing his cousins toys (and various other incidences). Not one peep the entire car ride home, but as soon as I carried him the house, put his PJs on, brushed his teeth, and carried him upstairs, he broke down....because he didn't get his chocolate milk. (not too mommy dearest, but like I said...)