40 yo mom, 150+ to lose, at rock bottom. HELP.

Totally revamping your lifestyle can be overwhelming. Start slowly. Just log what you are eating now and see where you are. Once you can see where you are, you can set reasonable expectations for yourself. You are not magically be satiated on a 1200 calorie diet if your body is used to a 3000 calorie diet, so I'd advise against going there. Chances are your MFP calculator won't tell you to go there either, even at 2lb/week which is safe with your loss goals. Follow the plan, trying to jumpstart it or go lower than suggested usually just leads to frustration and eventually quitting.

Exercise: Calories burned from exercise can vary wildly on the app. Best to have a HR monitor to calculate calorie burns and manually overwrite the MFP values when you log exercises. This still isn't 100% accurate, but its a good place to start. I also usually only eat back about half, but that is because I'm a little lax with weighing my food and the off set works for me.

Logging food: Measure your portions, weight (grams) is a better measurement than volume (cups, tablespoons, etc.). Volume will still give you an idea of a serving size. Be reasonable, if an entry says your cupcake is only 100 calories, it probably isn't for a full sized cupcake or maybe it's somebodies modified recipe. In other words if it looks to good to be true, it probably is.

No food is bad: No food is really off limits unless it triggers you to crave it more. For me sugary foods make me crave sugary foods ALL DAY LONG, so I limit them. Pizza is a biggie for me, I need at least 3 pieces to feel satisfied, so I plan ahead when I want it so I have room in my day for 3 slices. Planning, yes planning, is key, but the degree to which you plan can vary. Some people prelog their entire week, some their day, others tend to always eat the same things. These are great ways to succeed, and a great place to start. I've been doing this a while, and have a good idea what the things I like to eat "cost" calorie wise per my size servings so I'm more relaxed about it. I do plan around, and prelog, special events or certain high calorie meals. If for instance I'm going to have a big pasta dinner, I log it in the morning to see how much I have left during the day. Then I eat light during the day and try to get in a workout so I can stay within my daily allotment.

Modifying Recipes: No need to forgo favorites, there are ways to lighten up most recipes. MFP lets you enter your recipes and calculate how many calories there are in a serving. It takes a little time to enter it and to determine what a serving is for you. A scale is your best friend. Some of my favorite dishes are pasta dishes (which is calorie dense). I still eat spaghetti, but I mix it 50:50 with spaghetti squash to cut down calories and still have the volume and mouth feel I like to eat. For pizza I will use a burrito flour as a crust and top with my favorites. I like real cheese so I don't skimp there, but many people are very satisfied with low-fat/ lower-cal cheeses. It all makes a difference.

I'm 48 with 2 teenage girls (on in college one in HS), and still have about 50 pounds to lose. I set my loss goal at 1lb/week because its sustainable for me. When I was in my late 30's early 40's I lost about 40 pounds through intensive exercise and a very strict diet. I eventually couldn't maintain that level and everything just went south, then I got sick and life happened. I put more weight back on. I'm down about 20 pounds so far and slowly whittling away at it.

Just a few things that work for me. Best of luck. Feel free to add me as a friend if you'd like.