The dilemma of enlightenment

As a lay Buddhist, I know it is almost impossible for me to attain Enlightenment in this life. So if I keep enlightenment as a goal in mind it creates frustration, as I am not progressing in meditation and, life seems hopeless as Enlightenment is an impossible pursuit. However, if I don't think of enlightenment then I don't have any good motivation to do meditation and keep the precepts. How should I get out of in this confusion? Life as a Buddhist seems almost unpracticle. Any advise?