One should be a very selfish person in regards of If someone doesn't care about you, you shouldn't care about them. If someone doesn't remember you, you shouldn't remember them either. If someone is quick to reply to your message, you also should try to reply quickly. If someone leaves a message unseen, you should also ignore it.
No matter how free you are now! If your life goes on normally without other. Then your life will be normal without them. Priority should matters to you.
As much as one give you priority, you also should give same priority.
(No offence , personal opinion)