Not eating. Any ideas why?

Technically this is my boyfriend's kingsnake. He has always been weird about eating furry prey. He is nearly 4 years old now and has been a pain to get to eat the right sized prey. He is big enough to eat weanlings or small adult mice. But more often than not he will refuse to eat them! So after a few weeks of refusing we cave and give him peach fuzzies which he always sucks down like there's no tomorrow. But I never give up on the furry food. Sometimes he will eat them. But lately things are not normal. Well normal as in his case. He has also been refusing the peach fuzzies. We even tried giving him some pinks and he wouldn't touch them. This will be 3 months now that he hasn't had a decent meal. In that time he has only eaten 2 peach fuzzies. I thought he might be too cold. So I upped his temp a little. It didn't help. I thought he might be backed up. I gave him a bath for 15 mins. Nothing came out. He doesn't appear backed up either. He doesn't feel lumpy. I can't figure out why all of a sudden he doesn't want to eat anything. I know he can go a while longer without food. But this is worrying me.

Any ideas? My last resort would be to take him to a vet. Though there are non in my area that know anything about reptiles. Back when I got my first snake I called vets all over the state and a lot of them even hung up on me or threatened me not to bring a snake into their office. So the few that will see snakes don't know anymore or even less than me but "are willing to learn".

could naturally be going into brumation, he doesnt look to be in any kind of bad condition from the pic u posted so id say just keep doing wut ur doing.

It is not uncommon for to take a longer eating break.

I'm experiencing it right now on several of my , and it's time to hibernate soon.

One way that has worked for me to get them to take bigger food, are to lie what they usually eat into them with the new bigger food item.

But as mentioned, your snake does not look thin.