Well it might be difficult on your side, but it also means you are like any of us, who sometimes need other people opinions too. So, it's totally okay to ask. :)
Anyway, I THOUGHT :
First, well I don't like a cheater and would've thrown them out of my life if they are cheating on me, BUT if it is my partner who I deeply in love with, no matter how it hurts me, I would want the best for them.
Tell me that I'm a fool. But that's me. A fool who is in love.
A lot of people acting quite different when they are really in love, including me myself.
Back to the topic.
In your article, you didn't quite mention clearly what the problem is, so I couldn't exactly give the so perfect answer.
But I tried to give the best I could.
She has been lying for a short time, dug a hole, and duh..
If you really love her, tell her exactly what's on your mind, tell her you care for her and do tell her you want to know if she's okay.
It's okay, step by step you can do it. The first step IS difficult, but don't worry you're getting there.
You can invite her on a lunch maybe, while you try to say these things to her.
Anything can be given as a present for her, but don't you think it's gonna leave some sad memories about the past although at the same time happy memories of you guys together?
IF she's cheating on you ( meaning: an affair with other person ) then you would rather NOT. Her couple might be asking about those present later if he found out about it.
But you can also ask her whether she want to take the momentum or not. If she takes it, fine, she doesn't take it, fine too.
Don't dwell on things too much even if you can't help but think about it. TRY to think in a calm mind. It 's way better, I tell you.
Well, that's my opinion. You're welcome if you do thank me. ;)
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