I cannot emphasize enough to focus on you, your needs, your values and your newfound freedom. I know looking at this as if it's freedom is a stretch in the beginning but let's face it, you can either dwell on the idea that you believe something is missing or you can acknowledge even if that's the case you choose to focus on what you've gained in all of this. You have a chance here to find yourself without interruption and interference of a spouse or significant other and at the moment you do not have to share time or your energy. Even though that is not what you want ultimately it's good to see the silver lining in everything we have.
Also stop focusing on others and what they have, what they are, where they have been in comparison to yourself and how you lack whatever it is that you focus on. This only serves to make you feel less than they are and it feeds the jealousy, feelings of inadequacy and ultimately, depression. It will take work to shift your thinking of course and it's not a flat path, but at first an uphill battle but it is one that is not insurmountable. Besides once you are successful in finding yourself, trust me, all that other stuff really pales in comparison.