We can’t say ‘absolutely cold’, because cold is relative and subjective. That is, there’s no definite value that makes something cold, and the range of ‘cold’ covers a wide range of degrees.
However, ‘freezing’ is an absolute, or specific, value, i.e. 0 degrees Celsius/32 degrees Fahrenheit.
‘The room is too big’ means that the size of the room is excessive for your needs, and the extra space will actually create difficulties for you. It’s so big that you need the room to be smaller.
‘The room is very big’, however, is just a comment or observation about the size of the room. You’re simply commenting that it is indeed a large room. However, you’re not stating that the size is a problem or anything, it’s just an observation.