Yearning for something you let go of

Do you ever just love someone so much that you end up losing yourself in the process? Like you’re so focused on helping them in their life that you forget to have your own? And because you’re impulsive and very stupid, you end up trying to run away from them and in the end you let them go; but then you start to wonder why they never tried to hold onto you in the first place? Then you start overthinking if the break up was really your fault or if they actually never cared for you? ….Is it just me? Or-..?