You absolutely must understand that the suggestion(s) that are meted out are for the benefit of the work, they're not meant as a personal attack on you. When someone that is not you reads your story, they will have opinions - it is the nature of being human. Venturing suggestions for improvements is (almost) always in the spirit of creating a better end product. The people that you trust enough to ask for their thoughts are usually the ones that have your best interests at heart, right? That means that you're going to have to disassociate at least a fraction to prepare yourself for critical feedback.
Take a moment to read the entirety of the critique before you jump to defensiveness. This one step alone can save you untold agony. Read it twice to make sure that you understand what the reader is saying, for all that. If there are a great deal of changes suggested, take some time to imagine the story with the changes that have been offered up - would you have written it that way, had you thought of it at the time? Would the changes make your story something other than you'd envisioned? Do you feel like the reader just "didn't get it"? If that is the case, then you must seriously consider that other readers will have the same experience and you may need to revise it anyways.
People will always view something from different angles. When you're asking for help, you don't turn an offer down just because it wasn't phrased as you would have, right? This applies to feedback about your book, too! When you approach it from the defensive, you will not be able to absorb and understand how to best utilize it. If someone asks an honest question, ruminate on it for a bit before you answer. The best cure for defensiveness is to think before you speak.
Also remember that you do not need to incorporate any of the changes suggested by your editor/feedback-giver/writer's circle/mom. It's your work and your vision should be realized. I should add, though, that spelling and grammar changes are probably best left modified - you'd be surprised at how many authors don't use the correct to/too/two or they're/their/there. Or maybe you wouldn't. Suffice it to say that when you're asking someone for their thoughts, it is always up to you to utilize that feedback or not. You have the power!
Your readers will always have opinions. They may vary wildly from your own. Be open to the different points of view you may be exposed to, it is only in the best interest of your work. Your friends, family, and editors really do want to see you succeed. Believe that!