I think she looks at them as 'work friends'? And it is very obvious that Christine and Allysha are really good friends, it was also hinted by Alyssa herself that she just tagged along with the trip.Why does Alyssa look so bored and over it in Christina and Alysha’s Paris vlogs? She seems so stand offish whereas the other girls are having the time of their life and are actually interacting with each other?
It's really sad, she was probably so jealous of Christine's Paris engagement and her ER, and Christine and Allysha's closeness so much that she was just salty during the trip. And also she really had to let Marco send her flowers in Paris too! Talk about insecurity, Alyssa!
(Christine's ER, it was made by Francisco the Jeweler, an associate of Peter Marco Beverly Hills)