<human>: From 22m.

Last night she reveled to me that during our first month together she was still messing around with her Ex of three years. I'm not sure how to respond to or handle the news. She said that she has cut ties to him besides being friends on facebook. 
My personal opinionis split, one side says to just move forward with the relationship, its just a hitch and she expresses regret.
The otherside asks what does this say about her? What else will she hide? Did she not think I was worth dropoing her Ex at the beginning? 

Its really hard to think about becuase I've emotionally invested in our relationshop so much.

Any advice or guidance you guys provide will be appriciated.

Can you provide a brief overview of the text?
<bot>: girlfriend of almost 8 months told me she was messing with her ex of three years until a month into our relationship. I don't know how to handle it.