I now view the film more as entertainment rather than a history lesson.
With very few exceptions, movies that center around a historical figure or event are rarely ever accurate to a high degree. I often fell into the trap when I was younger where I would often assume that a movie would be as close to historical fact as possible. It was only later that I realized that a movie at its core is really just a form of entertainment and everything is catered to serve the story. If there is a historical fact that is seen to not mesh well with the story that the writers and directors want to tell, that fact will be altered or omitted.
With that said, "Lawrence of Arabia" is a great artistic achievement but it should not be used as a basis for understanding that period of history. Books will always be the most important source when you want to know and understand the facts.