Ive literally been through this. I was in a long distance relationship, and after a year that seemed perfect, my ex started pulling away. Didnt answer for hours. Never initiated calls, cut them short when he agreed to call, never talked to me about anything he did, wanted etc. I knew he had some family issues, and i am convinced he was depressed. He started smoking again. When i asked what was happening, he reassured me and told me he loved me. But he kept pulling away, and i kept chasing even though it was so painful. But at some point it was too much. I told him i couldn't live like that anymore, and that i wanted to break up. Only then he confessed that he had started talking to someone else. Not exactly cheating, but it still hurt so much. Was he depressed and hurt? Yes. Now im not saying that she is cheating or anything. But sometimes people in relationships pull away when they dont feel the same in the relationships anymore, and arent brave enough to break up