Most Helpful Guy
Emotional abuse is, for me, if someone is constantly putting you down by belittling you or downplaying your worth. A less recognized case I'd say is also the absence of overt emotion (or the presence of faked emotion) in a respected/significant other. Especially if you want to show your emotion but a respected/significant other doesn't approve.
It's rough to go through it as a child because you don't really realize that something's wrong until later in life. Then you gotta go through all the "fun" hoops of therapy and whatnot depending on the severity/duration of the abuse.
Most Helpful Girl
I consider an emotionally abusive relationship as someone who doesn't believe you're entitled to having your own opinion or speech and someone who keeps hurting you mentally and emotionally, making you think you have no choice but to stay with them. The abuser usually makes their partner feel insignificant and weak, and someone to order around and make the relationship feel more like an ownership rather than 2 constructive people being together. Also abusers will try to manipulate the victim's feelings by doing things like guilt tripping them, threatening them, making them think they have no other options, etc