People may misinterpret depression as disinterest, or being rude & flaky or purposefully ignoring them and being self-absorbed instead of the caring friend/family member that they are- which sucks because that makes the said depressed person feel worse when they then get rebuked or ignored as a consequence and they feel even worse and hate themselves even more - all they were doing were trying not to be depressed and didn't have time to be engaging and remember something they talked about with someone or forget someones name- It seems a lot of people still don't realize/know that depression causes one to be more forgetful and have low energy and have slow thinking in general so I guess depression can be selfish in the fact that you don't think of others because you're so distracted by the negative thoughts and the pain you feel inside. Plus usually one doesn't want to be a downer (or at least I don't) and tries to be 'happy' and stay positive for the sake of being around others because most people either misinterpret their behavior and take offense or don't know how to react/what to do and feel uncomfortable anyway around people who are depressed.