Thumb Sucking & His Hanky

Kyrell did not cry today (good boy), let teacher Sara carry and kissed me goodbye. When I fetched him, he was in the music room and the moment the door opens, he rushed to me and show me his hanky (as if telling me first instead of me catching him with it), told me they were watching "Mr Bean". Teacher Salina came out and told me that Kyrell actually asked to watch "Mr Bean" (aiyoh) and shouted "Hurray!" when its turned on!!! This little boy is getting assertive in what he wants now...

While packing his things home, teacher Sara told me that she has not been successful in taking Kyrell's hanky away. Kyrell is still refusing to 'surrender' his hanky after he woke up from his nap, this has been on-going since he started N1 in Dec. I have told the teachers to take away his hanky, this way he won't suck his thumb because it is getting BAD. The skins were broken, there were cuts (he bites, not only sucks), his thumb nail is soft (constant soaking in his saliva) and the bones of the thumb is crooked, no joke. I am getting abit worried.

He has been sucking his right thumb to sleep since he was months old so its been more then 1.5 years, imaging the damage. But the hanky+thumb sucking (yes they come together) are what makes him fall sleep, comforts him, in short, they are his security blanket. I don't even know how to begin cutting his habit off or just take his handy away altogether.. it seems cruel.

Even recently, I have tried to prolong the time to give him his hanky after his shower, the moment he's out of the shower room, he will be asking for his hanky, saying "hanky" repeatedly. If I still do not give immediately, he will starts whinning and crying, asking non-stop for his hanky "i want hanky, please mummy.." then like a drug addict going cold turkey, he will be sniffling, tears dropping, in cold sweat and sometimes mucus will be dripping down... OHHH....... how can I bear not to give in eventually?

Anyone has any suggestion or idea to contribute? I was thinking of just letting him cut off himself, he will one day, some day~
Or should I at least try something out? Like putting chilipadi on his thumb? But will it cut into the broken skin? Gosh...