I understand how you feel, i understand completely. You may feel like there was something you weren’t doing enough of, something that someone else did better. You may feel like you’re not good enough and so on. But the truth of the matter is, they weren’t good enough. You were faithful and gave them what you could, if that wasn’t enough for them, they weren’t the ones for you. If someone can’t be faithful and tame themselves to you. They don’t deserve you. So before you shed a tear over him/her, think of this, you gave them what you could and remained faithful, you did good in the relationship and you deserve to get the same in return.