Dreary day

So I'm sitting here, putting off housework, thinking of some long lost friends. I'm not quite sure why a dreary day makes me nostalgic, but it always seems to happen that way. I don't understand why some people are only your friend when it is convenient for them. Like work friends, as soon as you are no longer in their view from day to day, you slip into a void. It takes a lot of effort to be someone's friend, but I get tired of being the only one who puts in that effort.