私も行かないと。
I understood it as "I also won't go." But according to Tae Kim's guide and Google Translate it is read as "I have to go too." Why is that? I assume と has something to do with it since removing it gives me what I understood of it in the first place or so sayeth Google Translate.
For the full context:
A:行かなくてもいいよ。
B:だって、みんな行くって。私も行かないと。
Yeah. What I understood of it does not make sense in this context.