Your life is full of relationships. That's truly where your happiness will be derived from.
Now, if you don't watch closely; these relationships can take a turn over night, or at least it might seem like that. In reality though, it was a series of compounding decisions over time that developed this distance within your relationships.
If you don't constantly make sure the ones you care the most for are getting their needs met and you are being the person they need you to be at that moment in their life. Then you'll look up from the pursuit of your own goals and find yourself all alone with no one to enjoy your success with.