As I understand it, emotional abuse is behaviour which is used to gain power and control in a relationship.
It can include: insulting, criticising, threatening, gaslighting, ridiculing, shaming, intimidating, swearing, name-calling, stonewalling, lying, belittling and ignoring.
Are there things that you say which could make her think this? Based on what you have said in your post it could be things like:
"Why doesn't he get a job?" "
"Why are you working so hard just to pay for his gambling?"
"We have had to help you out so many times."
She may interpret all of this as criticism of a man she loves, intimating that she has made a poor choice.
Is she having counselling for her depression? A counsellor will be trying to get to the root cause of her illness but often people will avoid naming the real problem and some therapies will often look to blame parents.