The truth is, I don't know. The story of our relationship isn't written yet. I suspect it has about as good a chance as any marriage. Couples break up because of basic personality conflicts, stress over money, work or kids, cheating, or simply falling out of love. Having an open marriage is no more a death sentence for our love than having a baby was. Some couples break up when a new element is introduced into their marriage while others don't. It's a simple as that.
I know couples who never strayed from faithfulness and still ended up in divorce. I know couples that blame their breakup on swinging. I know acquaintances of my parents who really enjoyed the 1970s, and rumours of their wild key parties are legendary. They're celebrating 50 years of marriage soon, and are the sweetest, most devoted elderly couple you'll ever meet.
I'm not 17 anymore. If I meet someone I have a crush on, I know it's lust, not love. And if it moves into love, that's ok too. I might find someone I feel is a better partner for me, and not want to be with my husband anymore. Will he fall in love with someone else and want to leave me? That's a possibility. But I see it as a possibility in traditional marriages too. My husband might work closely with a co-worker and develop feelings towards her. It's not a problem that's unique to swinging or open marriages.
Am I deluding myself and setting myself up for failure? I don't think I'm any more deluding myself or destined for disaster any more than a monogamous couple is. It's clear that monogamy does not guarantee a successful marriage. Neither does having an open marriage. I think a successful marriage is built on respect, love and open communication, not whether you do or do not extend your physical or emotional self to others as well.
Am I tempting fate? Will I someday regret having opened this door? I haven't regretted it yet. Our understanding of each other is better than ever, and our sex life is full and varied and fun. We're not out every night trawling for sex with strangers - 99% of the time we're having sex with each other. And despite the challenges of both of us working in full time, demanding careers, and busy kids and travelling and keeping up with the house and the dog and friends and family and exercising, we're still having sex almost every single day, sometimes twice. It's a great way to fire up for the day or wind down, to connect and check in with each other and laugh and have fun together.