I really don't think the one that truly loves us can leave us in anyway

A person who truly loves you wouldn't want to be away from you for months. They wouldn't even want to break up with you by thinking that you might be with someone else after the break up and they wouldn't want to lose you. A person who truly loves you will make an effort for you. They make an effort and don't shy away from emotional investment. If they leave, it means they don't love you, it just means they had some feelings for you. And I'm sorry, but if they come back after months, it's because they haven't found someone better than you yet.