How could something as beautiful as life, end finitely without an afterlife?

I believe there is nothing after life, I don't know why we have it but I accept that instead of spending time thinking of reasons why we should be grateful to whatever caused it and experience as much as we can before the time we have is up ... people seeing deceased family members is one that my father believes because he saw my grandmother the night she died in his room with my mother who also saw her, I can't explain it and get goosebumps thinking about it, but considering how smart the human brain is it could us playing mind games