I hear parents harping on their kids' outcomes and results often without them admitting to themselves that the discord in the marriage or coparenting relationship could be the main reason. It's ALLLL related as much as we wish it wasn't.
Blaming the other parent, undermining each other, avoiding making agreements and sticking to them...just generally being all over the place as leaders is very confusing to kids and it's not a surprise that they shut down, think less of you, act out and ignore you when you're finger is pointed at them all the time.
That's one thing about kids, they see right through bullshit and they don't have respect for hypocracy.