How about start by figuring out where you are. The tools are simple - you have a scale, now add a tape measure and a postal scale? If you don't, or your BF's mother doesn't have them, you should be able to find them at the dollar store.
Also, get something like a little notebook.
Now, take your bust, waist, and hip measurements, the upper arm, the thigh (maybe 2 thigh measurements - one 2" below the hip and one 2" above the knee), and weigh yourself. Repeat measurements once a month (okay the first month, do it every day - but you won't see a lot of change
If you weigh yourself every day, as most of us do when starting to change everything, you'll notice a daily fluctuation, but over time you'll see trends. That's the important thing.
Write this information down.
Now you know where you are.
Now start looking at what you're eating.
If dinner was mashed potatoes, meat loaf and corn, write it down.
Figure out your portion sizes are - use the postal scale in the kitchen to give you an idea of what's going on.
Write all this down.
Write down all your exercise, every minute.
Now, use the Web to look up the calories in for the food , and a calories burned calculator for what your exercise.
Maybe, the next time you have this dinner, you could offer to help cook, and ask if you could have canned green beans in addition to the corn - then you eat green beans and skip the corn.
Or buy a pack of spring greens seeds, and grow a patch of salad!
Take it slow, honey - you have your whole life to do this.