I am in that boat. She is vegetarianish (fish and eggs are eaten).

After I started gaining weight a few years ago, I started trying different things. Got fatter trying to eat like her, but ate lots of bread and rice.

Switched to the Paleo-ish Slow-Carb diet from 4HB, and saw immediate results. Learned more about Paleo and adjusted accordingly (got rid of the beans I was still eating a lot of), and had even better results.

She still gave me grief over everything, but I'd shut that down quick. She would say things about cholesterol for eating too many eggs, etc. When I showed her that my cholesterol was already far lower than hers, and it dropped 30 points after switching to a flat of eggs a week, she doesn't talk about that anymore.

I have laid it down simply that she doesn't get to lecture me on eating anything when I am the one getting the results, and she is still having the same struggles she has had since she started this lifestyle of hers (as a child). I don't give her grief and scoff at the things she puts in her mouth, and she doesn't get to do that with me.

I just let my results speak for themselves.

After months of this, last week she told me that she was going to start adding chicken to her diet.

Baby steps...

My ex-boyfriend of 4 years is a vegan- maybe that's all I need to say.

Just kidding. For the last 2 of those years, I was paleo. We had based much of our relationship on food and we, in a sense, had to break that basis of being together when I started. At meals we would cook veggies together and then each take care of our own protein, but there was no longer the union of meal time that I love so much. Although he was incredibly supportive, it was difficult as our ideals shifted away from each other's. I do think it can work, tho, as long as there is respect for the other's choices, beliefs, and journey to health.

My wife was a lacto-ovo vegetarian. I was strict paleo. Her eating was based on some kind of misguided "It's good for me!" mentality. After a few months of rigorous strength training and Brazilian jiu-jitsu, which she had decided to participate with me in, there were very notable differences in our recovery rates. I got stronger and could recover from max effort attempts faster. She now eats what I'd call "paleo-flex" because it was never a moral debate. Her BF% has dropped by 5% in the last 16 weeks since she decided that maybe eating animals wasn't such a bad idea.

My step-mom is a vegetarian, has been for the past 25 yrs, yet my dad is a big meat-eater. Our meals growing up consisted of at least 2 veggies and a meat protein. The veggies were not a side, the meat was not the main portion. They were equal. The kids (me and my 3 step sisters) got to choose what to eat from what they had prepared, after we had taken bites of everything. If we chose not to eat meat, we ate more veggies, if we chose meat, we still ate veggies. I felt that this was the best upbringing because neither parent ever pushed their beliefs or feelings on us kids. They both shared their opinions and told us why they had each chosen their specific diet. I am paleo, one sister who is mostly vegetarian, one who is completely dairy free, and another who eats anything (mostly bread). Good Luck!

my husband is effectively vegetarian, but will eat meat if he knew the animal personally (and how it was raised and killed). we have friends who raise livestock, so he will eat that meat, but nothing if he knows not its origins. usually, i make my meat, he makes his veggie burger, and we share the veggies. its not that big of a deal.

ive only been paleo for 9 months or so. i had actually just started eating meat again when i met him ten years ago, and he became vegetarian very early on in our relationship. frankly, i dont know if ive ever been in a relationship with someone who was on the same "eating plan" as me. and no, its never mattered a bit because they have always respected my choices. if someone didnt respect the fact that i choose what food i put in my body, there would certainly be larger issues that would be deal breakers in a relationship. i do not respond well to being micromanaged. i have been lucky to always be with men who allowed me the space to be myself, for better or for worse.

and we are very happily married, thankyouverymuch. dietary choices are such a small part of our partnership.

ETA: a friend of mine just said in a blog posting- "Food is the third most enjoyable thing in my life. Friends and family are number two. Friends and family with food are number one. Simply put, if I have to choose between friends and family or food, I’ll pick the people whom I adore. But I am fortunate to have the ability to be greedy and have both and thus I choose the combo!" and thats just how i feel. im not going to end up divorced in a crappy apartment alone with my paleo meat locker.

Stranger things have happened...

Full story here... http://bayourenaissanceman.blogspot.com/2009/10/talk-about-extended-family.html

Mark Sisson and his pescetarian wife Carrie.

Not in a relationship, but anectdotally, all the combo relationships I've seen are either dual vegetarian or subsequently divorced. Usually what happens is it's the female that's vegetarian, and the male changes over to keep the peace.

It may work out for some, but it tends to turn into a severe conflict from what I've seen. Any regular argument turns into "You kill and eat Bambi", etc.