<human>: My GF(19) of three months found out today that her ex of 3 years now has a 'fuck buddy'. I met her when she was still going out with him but they were 'on a break' and she said she had been planning on leaving him for a while. I realised I may have been a rebound when we first started dating but I got over that because she seemed well and truly over him. Now she's found this out she's really upset and I have a feeling she isn't as over him as I'd have liked to think.

Not sure where to go from here, she's my first girlfriend so I have no personal experience to draw from with regards to feelings about exes so I could do with some advice!

Thanks.

Can you provide a brief overview of the text?
<bot>: Do I bring up to my girlfriend the rebound issue? Or do I just support her and see how it all pans out?