The shock of adultery will have you insane. Be conscious of that. You are insane. So try to get back to sane.
Give yourself all the love you gave to your partner. Give yourself all the benefits and gifts and time you gave. Pamper yourself.
Treat yourself, as previously stated, as surviving a horrific accident. You need time to recuperate.
What you need to do is, unless you really have a good place to go, stay where you are.
If the cheater wants a second chance, say okay. Whether you mean it or not, go for the pre-awareness status quo ante.
You need everything to be as it was, because you are not.