One's perceptions of any discrimination that is happening could either be entirely real, partly true, or fiction, depending on if one's judgment was clouded at the time, the actual thing that happened that may or not be discriminatory, or as based on the intent, action, inaction or behavior of the other which could be misinterpreted or real on the surface or by not learning or learning more.
Sometimes though discrimination will be obvious, if the worse treatment seems clear from any rude, offensive or harsh spoken words, expressions, postures, or actions showing being singled out because of race, age, disability, sex, nationality, religion, etc.
Other times discrimination can still occur if it is hidden more or seems less apparent on the surface, like if that offender with harsh views or generalizations keeps silent, avoids that other or other class, or votes against such or wishes bad things to happen to them based on quick judgement or inspection, etc.
But let's not overlook discrimination can occur when those with real or perceived less social status standing are involved, too, like for poor persons who can be pushed down further by those in power, or assumed by society as less able or worthy, and discrimination can occur within the race, for instance as well, if one does not conform to the stereotyped image there or to their culture norms.
So whether the discrimination is real or perceived may depend on one's perception, if it is not blatant. Rare though will anyone admit they discriminate. They will try to justify their worse treatment of the other or put that other on the defense to take away from their own prejudicial views and unfair beliefs or actions. It happens way more than advertised. I know that, either one time occurrences or more, but a pattern of such behavior will be harder to deny or defend against.
In our case, my wife seemed at least initially discriminated against by a professional, from their comments during a matter assuming the way my wife looked (Asian descent) and because of her young age and friendly and talkative nature at that time she could not be disabled so they treated her unfairly after learning such by a look of disgust and immediate avoidance of her and talking to me that I picked up on.
It is surprising though that my wife does not get much other noticeable discrimination though in this almost entirely white community. Perhaps it is because I am white and so seems our children on the surface. Maybe those others are more afraid to say or do something stupid then, knowing I would likely call them out on it, as her and I are often together with the children when she goes out. She feels more harm will occur if I am not there.
Discrimination likely occurs a lot for mixed couples of different race or nationality too, but I have not heard of it against us yet from the general public. I know my wife's mother was against our marriage though, but too bad she could not stop it. She was very prejudicial as seen by her many statements during the early stages of the relationship. I tuned her out or sometimes would confront her.