"If it comes back, I think that Friday night is not a good night to be on"

In this quote, Amber Tamblyn is expressing her belief that if something returns or resurfaces, Friday night is not a perfect time to handle it. This could be analyzed in a couple of various ways. One possible analysis is that Friday night is generally seen as a time for relaxation and loosening up after a long week, so having to face a problem or issue on this night would be disruptive and unwanted. Another analysis could be that Friday night is a popular time for social activities and occasions, so having to deal with something that has returned might disrupt plans and enjoyment. Overall, Tamblyn is suggesting that Friday night is not a good time for handling problems or issues.