How do I know if my girlfriend is bisexual?

Question

We werent together at the time we did a 3some with another girl  I think she just did it for me but  I still question her we have great sex and  I know she loves me but its her best friend the way they are together questions me am  I just trippin?

Answer 1

I think the only way to truely find out would be ask her up front.  Speculating will only stress you out.

Answer 2

If she likes lez porn