Handling lies is a huge part of affair recovery. Lies are problematic for the cheater and for yourself.
One of the problems with the lies and double-messages that cheaters use is that after a while you may start believing them. You may find yourself filled with self-doubt based on what they are doing.
You may tell yourself that you'll never be loved or that you aren't worth loving. The lies and other crazy-making behavior lead you to start believing what they are telling you.
At one time, you could believe what they told you. Part of you wants to believe them.
When they start lying to you, it leads you and them in believing things that aren't true. It's bad enough that they lie to you, but when you start believing them, you suddenly find yourself sinking in deception.
Like quicksand, the deception surrounds you. You hear many messages, but aren't sure what to believe.
On one level the cheater has let you know what they are going through. At such times, they aren't sure what to believe either.
That sensation of being stuck is not just your imagination. At those times, both of you are stuck in the deception of lies.
The first step of getting out lies in identifying what are lies and crazy making behavior. Once you see what they are, you are less vulnerable to their impact.
It's also important for you to renounce and deny those messages. When they happen, ignoring them isn't enough. In your head you'll need to renounce them as "that's not true" or "that's a lie and I reject it".
The renouncing is part of changing the programming in your own head.
Another helpful tool is the video "Overcoming Affair Trauma", which guides you in changing your mind and body in the aftermath of an affair.