First time posting on here as need some opinions.
I have known my girlfriend for years but she has always been in relationships - we have a mutual interest and been friends and then in the last 6 months have got together. Relationship is all going well and very happy.
I am a straight male and I think she would say she is bisexual. She has had a relationship with a woman in the past.
My question and reasoning for stating this is that she has a strange relationship with one of her female friends which I find uncomfortable. They have been friends a while and are quite close, this girl is always texting her. My girlfriend says the other girl is straight but just likes to test the boundaries and flirts with her. The friend sends my girlfriend flirtatious messages including pictures (not nudes but similar). My girlfriend just says they have a weird relationship and it's always been like that, but nothing has ever happened between them. This girl regularly comes round to my girlfriend's house and sleeps in her bed (even though she has a spare room).
Is this normal and AIBU to tell my girlfriend that it's not and I'd rather this girl wasn't sleeping in her bed and flirting with her?
I feel that if it was a male friend doing these things, I would be justified in having a problem with it, but because they are both female I am made to feel it is not problematic.
Sorry if this post is not very clear, happy to answer any questions.