Nude photo???

I was at my mom's Saturday and stayed the night with her and my sister. I woke up Sunday morning to a snap chat from an old friend. We will wave at each other when we see each other, but we don't talk or hang out anymore. We do not snap each other. I am female just so that is clear. Her and I were inseparable from eighth grade to 10th grade. We grew apart drastically in high school. We have seen each other naked before because sometimes friends change clothes in front of each other. She has recently lost a bunch of weight and looks really good. I am married and have gained weight (280 lbs) I do not look good. She does have a boyfriend named Thomas, so I am hoping it was an accident, but idk. She snapped me a picture of herself topless. Idk why she sent it to me, her boyfriend was laying on the bed behind her I think, so idk if it was meant for him. I'm super confused. Anyone have any ideas as to why she would sent me this???

***added***

She does not answer my snaps when I ask her.