I thought we had a strong relationship

A woman thought they her relationship with his boyfriend was so strong even they are miles away from each other. For four years in their relationship they never fought. The guy always listens to her point of view and vice versa. She never thought that after all this years nothing can go between them. Then all of a sudden, the guy changed his ways by finding away to argue with her, he is not communicating with her than their usual schedule. She asked him a direct question, if there is another woman in his life? And he frankly said yes. But he doesn’t want to breakup with her because he still loves her. Huh?

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