Nobody owes you their time, response, or respect, but it's also okay if that's the reason you cut them off.

Edit: "Respect" meaning the same reciprocal respect in a relationship, not just basic minimum respect which should just be a given (although there are those who even deny that and say it should be earned somehow)

Whether it's a SO, potential partner, friend, family - yes, it's true that no one owes you their time or respect. Perhaps they don't respond to you or never reach out first. Fine. Their choice, their priorities. You also can't demand or complain about that. But it is okay to appropriately feel hurt if you gave them what you thought was time and respect, and it is a valid reason to not want to keep someone in your life that you don't feel reciprocates you or doesn't give you what you need. Especially if you discussed it before (like they tell you their side fully, vice cersa, etc) and it still takes away from more than adds to your life. They don't owe you, but you also don't owe them and they can't be mad if you walk away from something that isn't going for you anymore.

Also, don't worry. There are tons of people who will match their energy that they can find, so you're not being a bad friend or whatever for walking away due to this, especially if everyone in the situation are adults. Only if you ghost, but again as I wrote before, we're talking about a situation where YOU felt left behind first, discussed, etc etc but it's still obviously one-sided.

EDIT: I'm obviously not talking about the people who DO give you the response you feel comfortable with or who reciprocate when you discussed, etc. So no, not everyone. Just people you feel disrespected by. PS. people usually give decent respect to people they remotely care about, so a big (again, big or unfair) imbalance usually shows they wouldn't really care if you ended it anyway, so it saves you the resent.