Here's the cautionary addendum: weight loss is typically faster right when you start because you're losing water weight. it'll taper off and then you have the mental challenge of fighting through.
My advice would be to find a food tracker (there are plenty, I've used myfatsecret.com because it plays well with my phone) and try to achieve a balanced menu while limiting your caloric intake to something reasonable that will allow you to lose approximately a pound a week. try to ignore those calorie calculators that tell you you burned 4,000 calories on that one hour bike ride you just did. They're typically very inaccurate and can lead to some bad decision making on your part.
I agree with mcrow about supplements, unless you're not getting your vitamins through your normal diet.
Congratulations on doing it together though! That's probably the biggest key to success is having a willing partner.