It is hard to let go, but sometimes you have to realize that these experiences are also stepping stones for you. Not in a way to undermine your struggles and experiences but to show that things do get better. If someone you love does not love you back, does not give you the same energy back, and only serves to make you feel bad - you are within your right to heal from that and you don't deserve that kind of treatment whatsoever.
But ultimately, if this person will have no chance to be with you and support you, it is better to make the process to let go. As much as it hurts -- and trust me, I know, but it will and does get better. You will find the person who fits everything you need and deserve, and you will do the same for them back. Maybe I'm idealistic but I truly believe soulmates exist. Keep your hopes up and don't give in, life may suck but there is always that light at the end of the tunnel that will bring you back to your feet after you fall.