I do feel insecure

dear God, may I ask You why do I feel sad today?
why do I feel lonely, really lonely T___T
even at that time my brother was beside me..

yesterday my bestie's hand got surgery because her some disposition muscles get well soon :)
but I can't there accompany her, really sorry yesterday I'm not feeling well
maybe that's the first reason why I feel sad..but sometimes I can't understand 4 myself....