Humans aren't wired to have one mate for life and we shouldn't restrict ourselves with mores and social norms if you feel you shouldn't be with just one person forever.
Be comfortable, be safe, be resonsponsible, be smart, be cool and calm in all situations, be sexual, and if you're all these things you'll feel more free. This applies to all things in life, not just having multiple sexual partners.
I find that those who're turned off by swinging or become jealous easily aren't comfortable with themselves...but then I'm biased. :tongue:
Obviously, I've deep seated beliefs in swinging. It's evolution, man. haha