Time heals a broken heart. Each day gives you space. Work on furthering yourself: career, relationships, personal pursuits. In a few months, your life situation will have changed.
You may still have reserved feelings for Claire, but they will be bittersweet. Each passing day builds distance and you'll realize that after some time that Claire is no longer occupying your thoughts. The possibility of anything in your life involving Claire is off the table, and you've accepted it. That different frame of mind is what enables you to forget, forgive and move on.