You’d be safe now… and forever.

According to Nina, the only reason she still didn't let her fiancé touch her was that she wanted to leave something for herself. But Jessa's take on relationships and love was different, which confused Penny. On one hand, Nina's reasoning was valid and reasonable; on the other, Jessa's advice was just as valid. 

It was probably different for everyone.

Some might want to hold on to something—whatever it was—because it would be unfair to give away everything and be left with nothing. But Penny was never like that. She wasn't as practical as Nina or as daring as Jessa. 

Be it in this life or in the previous one, Penny had always given her all when it came to love. She had given her all: time, energy, mental and physical health, and even her freedom for the people she loved. If Penny could do that for the undeserving without asking anything in return, what was stopping her from entrusting her all to the very person whose entire world was… her?