<human>: I'm in a very loving relationship with my partner of over 1 year. We live together, 99.9% of the time get on like a house on fire.

I was helping her find something in her phone when I stumbled on a note - it looked and read like a message she had written to another guy from a few months back. The note/message was addressed to a guy's name - a guy I know she's friends with and messages quite regularly. I've often thought they message quite too regularly, but no reason not to trust her.

I only seen the long message for about 5 seconds. I caught glimpses of the blokes name (it was addressed to him), a few other details, and crucially, the line "I've always thought we've meant to be together". 

After I seen I got out of it quickly as I didn't want to snoop. I didn't say anything at the time.

I don't know what to do. I can't move past what I think I seen. If it is as bad as it looks then I'm pretty worried. Only thing is - I can't be sure. I don't know the context or the contents of the message beyond the little glimpses I had. I'm worried if I bring it up and I'm wrong that it'll blow up in my face. 

Do I ignore what I thought I seen? Or confront? Or something else? Am I overreacting?

Thanks.

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<bot>: I caught a glimpse of a note in my girlfriend's phone that looked like she was telling another guy she has always wanted to be with him...but I can't be sure.