Secrets
Some secrets are meant to be kept, even or actually especially in a relationship. An “innocent” thought, for example, might cause pain to your significant other if they knew but without taking any action upon that innocent thought and keeping it to yourself you do not hurt anyone really. The truth may be that your significant other knows, depending on how well they know you, and that’s fine we all know that we ourselves have thoughts we don’t always share and we don’t have to. so it’s not so hard to figure out that the other person has such thoughts too.
Secrets become a problem when they are being acted out, even more so when this is being done secretly. If you find yourself in such a position then you are doing something that you believe will compromise your relationship or your own image. If the truth and often such secrets come out sooner or later, is being revealed then someone often is going to be hurt in the process in more than one way. Betrayal is something difficult to deal with. For both sides often. After all, if you didn’t have a problem with the betrayal or the consequences it may have then you wouldn’t keep it secret.
Honesty in a relationship is important to an extent. Putting the other person down or making them feel bad (and yes we often can figure out easily what makes the other person feel bad) is something you sometimes can easily avoid by just not responding to something, or keeping your reaction neutral. It means to accept and respect someone for who they are.
We do not all have to agree on the same things, we are different people and have different personalities and things we like and dislike. For example to old “does pineapple belong onto pizza” question. You not having respect for the other person and/or accepting them doesn’t necessarily say anything about that other person and perhaps a lot more about you. The way you treat others is because of who you are, not because of who they are.