The process of de-cluttering can be easy or difficult, in part due to your attitude about it. Remember that all things have a useful life and when it's no longer useful to you, it can be useful to someone else. Don't be selfish and hold on to an item because you once loved it, even though you no longer need it. Respect the value of the item by passing it on to be useful to someone else. This approach should help in letting go of items that you no longer need or use, but are still in good condition.
Focus on the end result. Instead of feeling badly about letting go of items, perhaps some still brand-new, focus on the positive. You're giving yourself the gift of a new space for a new adventure!
The decision of donated versus sell depends on the item. High value, good condition items that are in demand can add extra cash to your new adventure (or pay for your Organizer). This process is more time consuming than donating, but can reap great rewards for the right items. Other items are best donated based on volume, size, or time constraints. Think of those less fortunate than yourself and help stock a place where they can get valuable and needed items.
Finally, think of de-cluttering as a positive step to moving on and providing others with items they need. Once this attitude is adopted, you just may find that you enjoy de-cluttering!