I've tried..and I've thought really long and hard about this and come to the very tough conclusion that Wally must have a friend, not only that but he needs people around him too.

His divebombing and biting have escalated, eg. he bombed and bit me 38 times yesterday in the space of 20mins which wouldn't bother me but for the fact that he's doing this for a REASON. It seems the more he comes out the more he wants to' assert himself'! Hormones or not, I really do think someone can give Wally a more fulfilling life. He isn't happy around me, no - one else just me.  He's fine in the cage, just impossible to be around and a frightened bird out of it. His sole motivation is to target me, bite my neck, ear, and hammer on the top of my head at every opportunity. Somethings wrong. He's not interested in doing this do this to anyone else so it's so obviously me that's the problem here.
Despite buying Wally as a friend for my previous bird because I felt she would be lonely I am against breeding animals for profit, especially as there are birds who so desperately need loving homes already, so I won't get another bird. Also if Wally can be with another bird who needs rehoming too then a home and companion could be found for 2 birds  and I think this would be a much more sensible solution than trying with another bird that may or may not work out.   It breaks my heart to see him like this. Seeing all the wild birds outside too displaying their courtship dances probably doesn't help.
As you say, he needs more than I can give him.  If I kept him knowing that he could and would I reckon be happier around more people and/ or have the opportunity to have a special friend and I'm not prepared to risk this for him it would be WRONG of me and plain selfish to hang on to him. He has so much more potential in him that he could be with me and not only would I be doing Wally a disservice but I'd also be taking away the future happiness of his future owner too.

You might say I'm a bad owner and a bad mum for givng him away but my friends and family have witnessed all this and have seen 1st hand what it's doing to us both, and they agree I'm doing the right thing.

I feel very sorry for you and your dilema at the moment.  Have you spoken to the helpline as Sheila suggested? You will find the number at top of page.  I wish you well.

Yes, I've spoken with Ann and things are underway.

Shiela,
Thanks for your helpful posting.
In response:
'Yes', I know it's silly season for birds, 'yes' I know these birds are very sensitive, 'no' I don't anthromorphise him, with any animal you have to understand THEM, we are already frightening enough to an animal and I always try and put myself in the animals's shoes.
'No' it doesn't matter what I look like (I thought it might be my bed-hair or clothing; I have considered everything, no different smellies on me or in house etc') he still dive bombs me, and 'yes' it is full on attacking, he's now leaning over and I think going for my eyes, I have to now duck everytime I move which is making him really frustrated as he can't now land on me anymore and deftly bite my ear or bang bang bang on my head. He's really got it in for me Added to the fact that for the past 3 days he's been out of his cage for 8 hours yesterday and well, he's still out today, I've had to leave him to his own devices and just go out. It's just impossible, he hasn't eaten anything all day, not since this morning 6am when I got up and won't go back in his cage, his poos are now runny but I'm hoping they'll be better by tomorrow. It's only happened since this aftrenoon, It was 10pm before he hopped onto my arm and went back to his cage a few nights ago. I'm even working my hours around him but in many respects the situation's just making us both stressed out and unhappy. He needs a new home asap, there really is no other way around it.
I KNOW that he would be much better with someone else, I've had friends and neighbours in and he's been as happy as Larry!!! I'm flummoxed!! He really seems to perk up and be interested in them, even starting to sing to them, he reverts to his usual happy self!! I know these birds are very sensitive and I worry that the longer he is here the more chance there is that he could get seriously messed up mentally.
And 'no' you don't sound harsh, you are just educating and that's a good thing.  ..But please someone call soon.