I am rather surprised at the tone as well. While we don't have both sides of the story, what facts we do have makes me think the law is an ass--if the black and white as described as the law is what it is. Must be some social worker blood is more important than family person who was very important somewhere.
I have no knowledge or experience here, but what I see is:
My boyfriend and I have had custody of his son since 2004
A longstanding relationship (aka bedwarmer) where the non-parent has lived with the child and:
doesnt remember to brush his teeth on a daily basis
who has seemed to perform parental functions to a significant degree. And:
I love this boy so much and have been there for him. We are scared. We were up all night last night worried. she has no clue about his conditional and special needs.
Who seems to have forged some level of parent-child bond. And who seems like the actual biological parent who has had custody is in favor of the bond continuing. It seems some case could be made the OP is psychology the child's guardian. Especially when dad is there and consents and:
mother gave him to us because she felt she needed to focus on herself.
since 2004.
When that is combined with the fact some case can be made the mom is unfit as she has had:
since 2004 when mother gave him to us because she felt she needed to focus on herself.
Prolonged separation from the child.
She has not been to school meeting since 2002 for him.
with an abandonment of parental duties.
His mother has played no part in his treatment or school, nor did she even know what his disablility was.
Showing a poor relationship with the child.
Again, I know nothing of California law regarding such matters, but is seems to me the OP is not playing some power trip but has a genuine concern for the child. Is there no case to be made here? Does she really deserve the derision? If the OP were a same sex partner of the father, I bet he'd have a case. At the very least, one he would not be hooted out of the room for asking about it.
I also understand both parents are ideally to have frequent and continuing contact. But I also know the Family code at 3041 provides for non-parent custodians without finding either parent unfit. I find it unlikely the law is as black and white as have been expressed so far.