бодой не разольёшь literally translates as "you couldn't split them apart with water. It pairs with the English idiom "thick as theives", meaning inseparable.
белая ворона is "a white cow", or something unusual and not like the others. This one reminds me of in English "white elephant" meaning a strange or quirky gift.
У меня едет крыша is literally "My roof is moving", but it is used like in English to say "I'm out of my mind" or "I'm going nuts"