Charaz,
Please come back & tell us how wonderful your son is doing & how much joy he is bringing into your life!

I agree 100% with the others. Your IL's (I'd call them outlaws though) have no say in naming a child that is not theirs! Your son is yours, not theirs, they named their own child/ren, they dont get to name yours as well..
I am a cow at times so to add fuel to the fire I think I'd be inclined to name your son your first chjosen name & then give him your Father or brother, or garnfather or someone from myour families middle name!!!
I'd hold my head up high when informing them of their Grandson's full name & I would keep my fingers crossed that it crushes them so they'd never have anything to do wiuth you again...
I believe yourself & your son are way better of with such interfering, abusive, pig headed, obnoxious bossy old farts in your life!!!

I am like Ryn, absolutely fuming at the screen..

Please just enjoy your son now & marvel in the way he grows because they grow so quickly & you can never get the time back!!!

Please also seek some help with your depression, as your son does need you & hopefully it will bring closer the bond between you, Dh & baby boy!!!

I wish you an eternity of happiness, be strong & believe in yourself & your own choices, your a Mum now & as the saying goes ... "Mum always knows best!" so trust that as a Mum to your son you are doing what is best for him, by giving him a name YOU choose!!!