Girls like her are dime a dozen!
Ask yourself. Do you still love her despite everything she'd cost you? the pain, the lies, the infidelity?
Do you love yourself and your kid? Can you live another year having a woman like her in your life?
It doesn't matter if you've been faithful to her all these years.. She's a liar, a cheater and a traitor. How can you still trust her?
Though it's really hard to move on and let her go, just do it! You'll be laughing at this situation once you get over it.
Better move on and feel the pain of letting go and longing than living your life in a LIE.