“A lie can only last for so long …”
You spend so long with someone and you think that you know them, you think that you know his feelings, and you trust his every word … his every move … and then he betrays you. What the heck do you do now? Boys are always looking for someone better. How do you look into your lover’s eyes and lie? She would rather hear the truth from you than anyone else, yet you stood your grounds and lied until she finally got the truth out of you. She shouldn’t have to do so much to hear the truth from you. The truth hurts even more when she has to force it out of you.
You know what the consequences are; that’s why you lied.
You took her trust for granted. You can’t fix a relationship and expect everything to go back to normal and get better after what you did. You did this to your relationship. I think that the best way for you to fix what you broke is to not fix it. Support her decisions and if she chooses to walk away from you, let her.