I am having problems with the Whirlpool GB2FHDXWQ02 Bottom mount freezer.

a few months ago the freezer was cold but the fridge was warm - seemed to be icing so I replaced the drain assembly and it worked for a month or so then noticed that no cold air was circulating from the freezer upto the fridge, noticed that the evaporator motor was not spinning, replaced the motor and the fridge seemed to be working - but found that the fridge crisper area was freezing so played with the freezer and fridge settings - couldnt balance so that the fridge was 37 degrees or so without the crisper being freezing - then after changing the setting the fridge stopped cooling completely........ran thru the diagnostic codes and didnt find anything and then did a Forced Defrost and could hear the sizzling of the ice defrosting and now have the fridge back down to a cold temperature but trying to figure out what the cause was so that I don't keep having to worry about fridge not cooling especially if I was not home to catch it. Would like to Fix the problem vs spend money on a new fridge if its a simple fix.