Yes, cycling
can absolutely kill your love life(if you let it). If your penis goes numb, while riding the bicycle, something is wrong. Stop, adjust the seat and if that fails get a seat designed to relieve pressure on your nerves. BTW, don't let somebody else tell you what's up... the problem and it's manifestation varies from person to person... eventually it will effect everybody it just depends how long you spend seated on the bicycle, how much you weigh, etc.
Obesity can also kill your sex life... there is no special saddle for that.