Accutane didn't work? Wow. How long were you on it? Have they considered another round of treatment?
The swollen eyes and itching sounds like an allergic reaction. Were you putting anything new on your face and neck? Are you taking any medication, herbs, or anything for this or other conditions? Food really has very little, if anything, to do with acne, but medications can. Food may trigger your atopic dermatitis, though, so you might want to look into common food allergens and have skin testing done by an allergist. You also have to avoid environmental allergens.
I'll give as many suggestions as I can from my own experience. A lot of this you probably already know, but I'll write it anyway, just in case.
First, are you using *only* non-comedogenic products (or ones that specifically say "won't clog pores")? "Oil free", "dermatologist recommended", "gentle" aren't good enough. Even your acne washes need to say this. I have found that "won't clog pores" is curiously absent from most of the over-the-counter stuff. Since it takes two weeks for a pimple to form, this would be a perfect marketing strategy--clear and dry pimples now, while causing them in the future. That way no one ever stops using your product. This is only my suspicion--I have no actual evidence, but I still err on the side of caution.
When I say that everything needs to be non-comedogenic, I mean *everything*. Make up, face wash, body wash, hand soap, lotions, sunscreen, even shampoo and conditioner (if you can find it). This also means that your fiance needs to switch, too. I know it sounds extreme, but if my boyfriend uses a regular shaving cream, I get break outs from our faces coming in contact, especially around my mouth. This is after Accutane cleared my skin. I still need to avoid things that clog my pores or I'll still get breakouts.
Because of the atopic dermititis, you may want to make sure that your products are hypoallergenic, too. I know this means quite a bit of searching and reading labels to find hypoallergenic and non-comedogenic products, but it's worth it.
Also, the basics like don't over-wash your face (twice a day is enough) because irritating the skin can cause acne. Exfoliate the skin gently before applying acne medication.
Have you asked your dermatologist about procedures like Laser Light Therapy?
And finally: stress. Doing your best to relax and not stress about things can help, as well. Stress and acne have been closely linked, especially for some people. As it gets closer to the wedding, stress management may become more difficult.
Well, after all that, I hope something in there is new information and helps, at least a little.
Congratulations on your wedding. Just remember that your fiance loves you the way you are. I know the acne bothers you more than it does him. Don't let this stop you from living and enjoying your life. You aren't the only person with this problem. So many other people have been through it or are going through it right now. Know that you aren't alone.
Good luck. I really hope you find something that works for you. Please feel free to write back, even if it's just to ask for support.