Absolutely not. Rosie and Jasmin are clearly very close, and Rosie and Belle are very good friends. I am not sure how close Rosie is with the other 2 but Rosie is just like that. I guess a reason we have not seen her much with Blair yet is partly she is on a different floor and partly because she knows Belle is looking after her. It is true that last time when she arrived she switched from spending time with Belle to time with Jasmin. However she didn't stop spending time with Belle although their moments largely became tamer she did continue to spend many long nights out with Belle.
If you noticed although Angel was not keen on being touched (in her sensitive areas) by other girls and was a bit like a cat on a hot tin roof when she was with Rosie and Belle when they started touching, Rosie won her over with cuddles. Incidentally Angel exhibited the same behaviour when Belle was off camera on the balcony with the 2 men although judging by her voice she was watching whatever it was, and we shall never know, that was going on.
In conclusion Rosie is not playing with anyone's emotions, she is just being Rosie.