She could not get her thoughts in order, is this bi-polar?

My distant cousin in her early twenties, has just been admitted for mental health. She had a hysterical break down, and was not make any sense when she would try to explain what she was so upset about. Her thoughts seemed to be all over the place, and she was connecting unrelated things into one (for example, talk about how there is a lot of crime broadcasted on the news, but end with saying something that sounds like it was her fault for not doing enough to help). She seemed paranoid of figures of authority monitoring her as well. She was functioning as she normally would, surfing the computer, going out for a bite at a coffee shop, except if you would talk to her, her thoughts would be completely disorganized and unfocused. Needless to say, it was really distressing to see her like this.

I would say it came out of no where, but she had just finished a stressful college year and was beginning summer vacation. She has no job and went from high stress related to school (and poor sleeping and eating habits), to excessive free time at home (and over-sleeping, probably over-eating too). She would also smoke week, drink, and act promiscuously. At first, I figured she stood a good chance to recover to normality simply by changing her lifestyle, keeping busy, keeping stress low, not smoking, not engaging in as much casual sex, etc. We first thought it was low self esteem mixed with intense anxiety and stress, but now she is diagnosed with bi-polar disorder and is on meds for it.

I am wondering if it is hypothetically possible for someone who went through this to recover with no meds at all, by changing their lifestyle and getting friend and family support? Does this sound like something bi-polar would cause?