I think the most important question to ask is "How do you feel about yourself?" If you truly wish to change your weight, change your lifestyle. Reinvent yourelf. Don't do it for someone else, do it for you. You are the only one who will be with you guaranteed all your life, and thus, you are the only one you need to answer to. Generate an image of yourself in your mind and then begin to emulate that image. If you walk around telling yourself "I'm fat. I am unhealthy. I don't exercise. I eat unhealthy foods" then you are exactly right. If you start to think of yourself as a healthy person, your actions will follow.
Also, start slowly. Don't expect instant results. Go for a 5 minute walk one day. Make it 6 the next day. Then next day go for 10. Keep increasing the amount of time you spend being active. Keep it varied and do things you enjoy. I used to say I only ran when chased, but I started slowly and have worked really hard on it. I just ran my forst 10K in May and will be doing a half-marathon in October. It took a long time for me to get here, but it was worth it.
About foods, I am not sure what types of foods you are eating now, but you mentioned pizza, etc. Start by eating only at home. We all cook much more healthy foods in our own homes than they do in restraunts and fast food places. Substitute one helathy snack a day for a candy bar, cookie, or bag of chips. Then build from there. Check out some Cooking Light Magazines. They have great recipes in there and they focus on substituting fat and calories, not taste.
About this man who has said these things to you-once you get yourself ina healthy place, it will be quite obvious to you whether or not he fits into it or not. When you feel good about yourself, it is much easier to make the right choices for your spiiritual and bodily health.
I hope this helps.