I have to agree. Having another professional accountant to challenge your thinking and check your work is invaluable. The work of two together is worth more than the two individuals. Sometimes you get that kind of discussion with your auditor, but I find a peer's advice so much more practical and useful. It also helps that I'm usually not paying my peer by the hour!
Earlier this week I attended a meeting of an industry group. They bring together representatives from the various organizations in our industry. This, too, gives me a chance to check in with my peers. I can stay up to date with them, check our performance against theirs, find out what issues they face and what opportunities there are to work together.
So, this is just a little reminder: if you're feeling alone in your work, consider volunteering on the finance committee of a charity or getting involved in your industry association. You'll be glad you did.