Hi
Your "horrible before shots" don't look that horrible to me! I would think you will be able to tone up and make a little improvement by Christmas with your determination. Good idea to set yourself a goal and keep this blog of your achievement. I am sure it will be helpful to others to see how you go.
I gained 3kg during chemo and managed to lose those 3 plus 6 more over a 6 month period on Tamoxifen. I changed my diet a little bit at a time and exercised everyday. I have maintained that weight loss for 3 years (2 of them on tamoxifen and now 1 on Femara). I am currently doing weights to counteract effects of Femara on my bone density. Also hoping to improve my lean body mass vs fat ratio.
Good luck with your goals. I will cheer you along!
:)