Nothing works!

My Son just doesn't settle any more. He spends almost all day crying. Unless I'm not with him. He's so happy when I'm not where he can see me.

For example, if he's downstairs with his brother and dad, and I'm doing housework upstairs, he is fine. I will hear him laughing, and playing. If I go downstairs, and he can't see me, he will carrying on playing. But if he happens to be near the door, and sees me, all hell breaks loose. He will scream, he will throw things, he will bounce his head off the floor.

If he's in his bedroom, and I'm in my room, I will hear him move things around and playing. If I go to the bathroom, and he sees me, the tantrum starts.

Nothing I do will settle him. Nappy changes, offering him food, offering him drink, cuddling him, singing to him, reading a story, giving him his favourite blanket or toy... If I do try to cuddle him, he just starts hitting and scratching me. He even pulls my glasses off so he can hit me without them being in the way. Earlier today he grabbed my neck and pulled. The only thing I can do, so he can't hurt anyone (including himself) is putting him in the buggy, but even doing that and rocking it doesn't settle him. However, if I leave the room and his dad or brother are with him, after a minute or so, he's completely fine again... I've tried everything. My partner can see its upsetting me, but has no idea how to help, other than let me hide in our bedroom while he settles him, but then we're straight back to square one if he sees me again.

I'm tired. I keep trying. Nothing works. It's draining.