You should not lay around in self-pity after a break-up.
After a long time of unhappiness Lily breaks up with Mark.
Mark wants to work through his feelings after the break up.
Mark goes out with his friends and family and takes up new hobbies.
Mark decides the best course is to shut himself off from his family and friends and mourn his breakup alone.
Mark works through his feelings by relying on others and developing himself, strengthening his bonds and cultivating a better person.
Mark will isolate himself when he is at his most emotionally vulnerable preventing him from healing.