Hi Maria, welcome to the weightloss forum.
This is an excellent place to talk and have people listen who are interested in what you're saying.
On the True Stories site, we have a daily thread that we record all our daily food intake (the good and the bad stuff)
We also have a place to record our exercise for the day. It sounds like you have great determination and that's the key ingredient.
Too often people join the forum and in under a week they give up. This weight took years to build up and it'll be a long steady road to work it all off again.
Resistance Training Program
Train your lower abdominals first
Breath out as you crunch up.
If you have your hands behind your neck, make sure you keep your elbows back, and crunch up using your shoulders. (This will help prevent neck soreness)
Keep your lower back pushed into the floor or bench.
I know that some people don't agree with this but unless you are advanced, and have sufficient abdominal and lower back strength, or have a personal trainer or exercise therapist that is spotting you and can ensure that you're performing the exercise safely, you shouldn't be performing exercises that encourage you to excessively arch your back. Exercises like this are not for "newbies" that are just starting out training their abdominals.
If you're on your own and find in general that your back arches considerably when performing just basic ab exercises then keep your knees bent and closer to your body so that your lower back is pushing into the floor or bench.
Don't overtrain your abs. Three quality training sessions per week is ample. Remember muscle needs recovery time to grow. It's muscle growth that increases your muscle in your midsection. Overtraining will actually deplete the muscle instead of increasing it. So that you can focus on your ab exercises perform them on your cardio days or on non-weight training days.
Don't go overboard with perfroming loads of repetitions. Rather than trying to achieve 5 x 100 crunches per exercise, hold for a count of 2-5, each rep you perform using 4-5 x 12 burning reps. This will get you better results. Your goal is to damage the muscle to promote muscle growth for increased muscle tone - that is when you reduce your body fat you've actually got nice strong abs to show off!
Don' t just train your abs. You need to be performing a full-body program rather than only concentrating on your abdominal region. Direct your attention to training each body part so that you can a achieve a "toned and firm look" all over.