Help! Myths vs truths, advice, and being realistic

I am at my wits end. I've made some really, really stupid choices (put of desperation) such as eating 500 calories a day or eating only chocolate (this is a "diet") both of which were ineffective and caused me to gain about 5 lbs. I started to spend time on unhealthy forums that endorsed starvation and chocolate-only diets, and I now have a very unhealthy relationship with food. I want to do this right and I want to do it wisely.
So, please don't judge my past decisions :c
Anyway, I'm at my highest weight now, 105. I have 0 muscle at the moment, so my body fat percentage is higher than I'd like. If I could lose 10 lbs before summer, and then start gaining muscle over the summer, this would be perfect.
I'm 5'2, and my maintenance is ~1450.
What should I eat? I was going to eat 1200 calories a day of healthy food every day with a "cheat day."
How should I exercise? I have a treadmill, p90x, and bodybeast. I don't know which to do. I have fat concentrated in my thighs and stomach/love handle area. I reaallly need advice here.
Basically, it's interfering with my life and my studies. My clothes don't fit, as they fit the old lean me.
Please, and specific advice you have or tips, as well as estimates of how long this will take to lose 10 lbs, I'd really appreciate.
I want to start feeling healthy.
Also, I'm confused about eating often vs. eating in a time window, having a cheat day vs. not having a cheat day, eating back exercise calories vs. not, etc. There is so much contradictory information out there and I don't know what to do.
So, 10 lbs in 4 and a half months: possible? And if so, best way to get it?

First off all your goals are very realistic. And you can do this without so much worry and stress.

If that is what you have to work with, then I suggest Body Beast. It will be your best bet to build some muscle. I'm not familiar with how it suggests you calculate calories, but it is probably more than you need since you are female. If body beast has instructions for female lifters, then follow those and ignore my earlier suggestion about using MFP mainenance calories. These ladies can probably help you: http://www.myfitnesspal.com/topics/show/1009327-body-beast-women-s-group

Since you have them, I think doing a round of Body Beast to bulk a little, then a round of P90x to cut would be great for you. I'd suggest you just do exactly as they say - eat according to their nutrition plans, and exercise according to the DVDs. Don't try to outsmart the programs you have already paid for and don't try to come get more advice from the MFP forum - it will only confuse the issue. That will take you about 6 months, then you can re-evaluate and go from there.

Good luck! Of course feel free to PM me if you have any questions related specifically to my suggestions.

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Chin-Up Bar (alternative: resistance bands)
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First off all your goals are very realistic. And you can do this without so much worry and stress.

No they are not...she weighs 105lbs and wants to lose 10lbs...

And at her height that's not exactly unhealthy. It might be on the low end of normal, but that doesn't mean she's got a raging eating disorder and needs to seek immediate treatment. Some people have petite frames.

I figure she knows her body better than you or I. Depending on her body shape her goals could be reasonable. What I recommended was sensible and healthy.

First off all your goals are very realistic. And you can do this without so much worry and stress.

Recognizing the bad decisions of your past is important, this way you won't repeat them.

Are you sure you're eating enough? I know you're not very tall, but that's a pretty low calorie count. I don't want you to think you ever have to starve yourself to lose weight. Yes you can have cheat days, you can have cheat meals, whatever you want to do. You don't need to rush to get the weight off. 10lbs is not much at all. But you want it to come off the right way.

Good advice that you'll hear from a lot of people are that a mix of cardio and strength training is the way to go.

You can eat whenever you want, meal timing makes no difference.

You should try to lose half a pound a week, if that. I think you'd mostly benefit from eating a healthy diet in moderation, running, and lifting weights. After that just drink plenty of water and get plenty of rest. Keep it simple and make it something you can do for the rest of your life, instead of a temporary fix.

Mostly just know that you can do this. It's not as hard as you think and can even be enjoyable. It takes time, effort, and trial and error, but you'll get there.

Best of luck to you.

I recommended she up her calories, eat in moderation, have cheat days and cheat meals. If you think that's encouraging an eating disorder I don't know what to tell you.

At the height of 5'2" and 105 lbs your current BMI is 19.2 which is the low end of normal.
Maybe you should talk to a professional about your goals...

There is so much contradictory information out there and I don't know what to do.

Eat at maintenance and lift heavy. Don't worry about losing weight, worry about body composition and building muscle. That will get your where you want to be without starvation diets or being severely underweight.