You don't, and can't. All you can do is trust your own judgment and determine if the risk of him lying again is worth any reward you might receive. People can change, but it's difficult (especially without help), and unfortunately, most people don't, or won't change.
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Sometimes it is hard to get over being lied too. The only thing that you can do is to give the person another chance and try to trust them again. Try having a heart to heart with the person and let them know how you feel.
In my experience not in certain cases. It all depends on the situation. Ex. Did they lie to protect some one.