Hi Kutay,
Like Tom A, and many others, I have been in similar situations, just remember you are not alone and take support offered even when you think you don't need it. Over my years of 'adventures' in healthcare its probably the best advice I can give.
Anyway during these sojourns a couple of my hobbies,once I've been well enough, have kept my spirits up, drawing and photography (even if its just been reading), then when I recover I cycle and snorkel. However what came to mind is that all of these are 'mindful' pursuits and have the ability of taking you away from harsh reality. HCB was conscious of this and this can be seen in his fascination with Herrigel's zen in the art of archery (I hope I've referenced that correctly). Other books that can be helpfull, Marcus Aurelius Meditations, and the wee Shambhala Rumi anthology, particularly 'the body is a rose'.
One of the most beautiful recurrent sunrises I've ever witnessed, is in Autumn when I have been a patient on the 7th floor of the Mater hospital in Dublin, when I was well enough I had a wee Oly XA 1 with me to record it (an opportunity was presented) . As to Tom A's suggestion of making a book about the process, I completely agree with him and with some sensitivity I'm sure your team will let you do it (Your Oly trip is wee and discrete enough for this), but widen the brief a teeny bit and include, anything that you give witness to, during the treatment period (not just illness related).
Like yourself I have bairns, two wee boys and the youngest of the two was fascinated with my film cameras, so for his last birthday we got him an instax mini, well 10 films later, he loves it! once treatment is finished your wee man can graduate to the Olytrip.
Anyway, all the very best and keep yer pecker up!
Dave