Brandon,
I second what Al said about nutrition, I've yet to work with someone with body composition issues who was in fact "eating clean." Almost no one I know has cleaned out their system to have an objective view as to how certain foods effect them. I for one will be 6-8 pounds heavier the day after eating any grain, this isn't to say I gained that in body fat, but rather my abdomen and body has swollen from eating things that don't promote my strength.
Complete something such as the whole 30 plan: whole30.com and you'll have an objective start to see how many foods that have falsely been promoted as healthy truly affect you.
Weight gain, sleep problems, etc. are tied to diet, but many factors are contributing to your hormone imbalances that are creating these issues, have you found a qualified holistic MD to work with to ensure your treatments are effective and addressing all your systems? IMHO based on my personal experience ANY diagnosis will improve or dissipate once the system is functioning as it should. 8 years ago I was a mess on 5 meds at one point, now 60 pounds lighter, 190ish @ 6' 2", with a far greater capacity for movement and strength.
Sciatic pain - Running, swings, etc. not a good idea until this is resolved by a licensed professional. SFMA and FMS methods resolved sciatic pain I had from a herniated disc 15 years ago and I'm stronger and moving better than ever without surgery.
The obstacles (opportunities) you have in front of you will create an inspiring journey, resolve to truly change and address these issues thoroughly to stop the cycle of pain/frustration, etc. you've been on. All you have to do is improve 1% a week in these areas and you'll most likely be setting PR's in many areas of your life a year from now.