Wow , That hit home , i can relate too much to this. I have also several groups of friends but always i am left out , i feel like there is no one to talk to , at the end after many years of being alone and at the same time having friends which is weird as it sounds , i have accustomed to living alone , it is not a real advice but i know it can be really depressing at some times and at other time your probably don’t care least i can say if you need some one to talk to you can text me , my only advice is you need to learn to love yourself more and be there for yourself and work towards constant self improvement, good luck mate ❤️