You may think you know your spouse inside and out, but do you really? Do you know what they are doing when you are apart from each other? They say they are going to work or to the gym, but is that true? Trust is so important in a relationship, but if your spouse is doing any of the following, it might be because they are lying to you.

1. They start keeping secrets

Even though secretes are not technically lies, they are never a good sign. Why would they have information they don't want to share with you? Healthy marriages don't have secrets. If you find something out about them and they deny it or avoid the topic, there could be a deeper issue or a lie.

2. They get defensive

Does your spouse seem to get defensive over the simplest of questions? Do they clam up or snap at you when you ask them something? If you feel they are overly defensive, it might be because they are trying to hide something.

Perhaps they are hoping you will fight about one issue to keep you from finding out about another. Maybe they want to be left alone because they're scared of getting caught in the lie. If this is the case, it's not a good sign.

3. They change their passwords

While your spouse has a right to privacy when it comes to their electronic devices, it is not normal if they suddenly change their passwords and won't tell you the new ones. It's a sign that something is going on, and it's probably something they don't want you to know about.

4. Their schedule changes suddenly

Has your spouse's schedule changed suddenly? Have they always had a pretty steady routine, but now it seems you never know where they are, or what they are doing? This can be a sign that they are lying to you about something. If you find they are trying to confuse you or they are being vague about where they are, it might be time to find out what they are really up to.

5. They don't look you in the eye

Has your spouse been avoiding eye contact with you lately? Are they looking at their phone or TV when you are speaking to them? Do they look anywhere but your face when you ask them a direct question? If they can't even look you in the eye when speaking to you, then there is definitely something up.

6. They start breaking plans

Does it seem every time you have plans with your spouse they seem to get canceled suddenly? Can you not remember the last time you had a date, or even outing with them? If you can't seem to keep a date, maybe it is because they are afraid their lies will come out. Or perhaps it is because they feel guilty and don't want to be around you. They should want to spend time with you without fear of being discovered.

It's important to discuss these red flags right away. Do not be accusing - just ask them what's going on. It could be completely innocent, but it is better to work things out before they get too bad.