Two people when there is a match, we think and feel, they should also have an understanding of each other. You say all the time, but you must be concerned about some subject, it should have a reason.
When two people have the same thoughts and feelings we should have mutual understanding. You say that you have to care about you all the time. But it should be realistic.
Two people when there is a corresponding thoughts and feelings we have a mutual understanding. You said that you would need to care about you all the time. But some of it should be reasonable.