To respect someone means you hold them in high esteem or in high regard. In the military many times we were told even if you didn't respect the person you needed to respect the rank. Sometimes people have not done anything to earn your respect because they have treated you like trash. I've had people treat me like trash because I was a female or my ethnicity. Yet, their behavior towards me did not change my character.
You may have to dig deep for the gold. There may just be some gold in those hills if you keep digging.
Affirm people and serve them as you would want to be served. Be polite, kind, thankful, and listen to them. Care about their feelings, congratulate them when they do things well, be helpful, say please & thank you. Be courteous, take their feelings into account, consider & value their feelings, appreciate them, recognize when they're hurting, don't intentionally try to hurt them, practice patience, applaud their efforts, confirm that their opinion matters.
So, the opposite of respect would be hatred, disliking, detesting them, being repulsed or disgusted by them, showing contempt for them being dissatisfied or displeased with them etc. You get the picture.
So, if you are in a romantic relationship, a friendship, or in a family etc. where there are signs of disrespect. (I'm not talking about where someone hurt your feelings by not returning your text within 5 minutes or someone has stepped on your shoes accidentally). I'm talking about some serious deep-rooted mean-spirited disrespect then these are things that probably need to be addressed. Consider a safe space with a clinician, a mediator, a therapist to talk through what you are feeling and experiencing.
Continuing in an unhealthy environment is not good for anyone emotionally. Everyone deserves to live in a safe, healthy, respectful environment. Seek help if you need it.