I think every good startup needs a coach. A mentor, or someone that will drive you to work your tail off when the going gets tough. Being in business for yourself is not for everyone. You can make a good income working for others, and not much income is required to have a very comfortable lifestyle.
Someone who wants to own their own company should do it for far more than working for themselves, or "financial freedom". The infomercials selling you on the benefits of being your own boss only serve to satisfy the emotion of most people hating their job or boss.
As a startup expect to work twice as hard as a regular job, stress three times as much, and probably spend 100% more real time (real time versus goofing around on facebook at work).
My advise is to find someone to support you emotionally. Someone that motivates you. If you played sports you understand the true value of a coach is not to call plays, but to keep up the morale. Its tough with startups because first, real entrepreneurs are rare, and second most dont have time to focus on your business when they have their own to run.
Still you can find great support in: a former teacher, family, your spouse, employees, the right partners, and possibly others in the start-up boat.
Whenever I start a new company, i mentally prepare myself for the challenges it will bring, and when things get frustrating, i know to take a quick break, go for a run, and get myself motivated again.
Using the sienfeld calendar is another plus, and using excel to track your financial goals. (finances are how you measure the success of most projects). Last, teach yourself to respectfully hate your competition. Much like a basketball team, hate them because you are playing against them, but realize that at the end its all a game.