Okay, slow down a second. Did you discuss THAT with your doctor?
Losing 5 pounds per week for 12 weeks straight is going to be intense hell and also an unsafe speed of weight loss. Plus, the faster your body fat percentage changes, the worse your stretch marks are. With how much you want to be as beautiful as possible, do you want to be covered in stretch marks? BE SURE to moisturize your arms/armpits/shoulders/stomach/chest/biceps/wrists/thighs/legs/screw it, moisturize everywhere, at least twice a day, with a deep penetrating lotion with shea or cocoa butter.
Furthermore, that's... okay, look, basically impossible. I'm going to assume june-august means all 3 months full, so 12 weeks like I said. That's a deficit of 18,000 calories per week for 12 weeks. That's a deficit of nearly 2600 calories EVERY SINGLE DAY without any days used to rest and recover. You needed to have already started warming up for this kind of thing if you were going to do that, as someone 60+ pounds overweight and out of shape is not going to be able to start and sustain that pace. You will need frequent days off for your body to recover. Protein builds muscles, but only if you actually let it rest.
100% diets always fail, every time. Do not even try that. A "diet" is actually a long term consumption habit, not a temporary thing you do. It is better to be at 70% of a diet, than 100% - because you will psychologically and physically crash.
Plus, a protein only diet is going to counter-act the effects of blocking testosterone. And you're going to wish you were dead without fiber. Vitamins are not a substitute for fresh fruits/vegetables and portion control.
I am not telling you to give up on everything. I am telling you that psyching yourself up for this and then failing will be very damaging to your forward progress. You went from being lethargic to being excessively gung-ho about the future and you need to reign in your reality before something bad happens.
Don't wait til June, setting a deadline to start some massive project is just another hurdle. Start changing your life today. Stick with lean chicken and fish, water/unsweetened teas, fruits with low fructose content, vegetables high in fiber and nutrients, and BUY MEASURING CUPS AND MEASURE EVERY PORTION.
Doing that by itself will cause you to lose weight just breathing - adding in cardio a few times per week and some strength training will be gravy.
Edit: I just noticed you said it was a 30 mile round trip to work that you plan to bike or jog to every day in the middle of summer. Oh god. *facepalm*