When is a friendship over?

Ive been really good friends with my friend over the lat 5 years or more.And since she moved away she changed.She doesnt have no friends were shes at. She doesnt have a job.Or want one for that matter.But she never answers her phone.I feel puzzled she does this to me and my other friend.So im thinking shoudl i just sttop calling her all together.Since she seems so busy(yeah right) or whatever the reason is.I also found out she was making catty remarks about my life to my other friend.Nothing to bad but just the fact that shes talking ****.MAn why are friendships complicated sometimes.It totally annoys me