The 24-year-old actress began dating the goth rocker when she was 19 years old and even though their engagement ended last year, the 'Ides of March' star is grateful for their time together because she learned so much.
She said: "Just because a relationship ends, it doesn't mean that it failed.
"I don't think I would be the person I am today without him. He is inspiring. The timing was right and I felt a door was open to me to really explore, express myself and take risks."
Evan - who is believed to be dating British actor Jamie Bell - revealed earlier this year that she is bisexual, but insists she has always been attracted to both men and women.
She told Independent magazine: "It's funny when you suddenly realise you bought into a certain idea for so long. You're just raised with a certain idea of what a girl is supposed to be and what a boy is supposed to be. That is not necessarily real. It's just what you've been taught.
"I've always felt that way [bisexual] for as long as I can remember. I truly feel like you're just born a certain way and I feel the more people are honest about something as human as sexuality, the more it will stop being a big deal."