6.
Contract a disease.Although lesbians are at risk for sexually transmitted diseases like herpes, HPV and HIV, there seems to be less attention paid by lesbians to safer sex than in the gay male and heterosexual communities. A STD can not only kill your sex life, it can kill you. Protect yourself!
More: Safe sex for monogamous couples.
Sorry if this seems random, but I really like number six for some reason, lol. Witty, unexpected, and very true. Full article here:
http://lesbianlife.about.com/od/lesbiansex/tp/KillYourSexLife.htm