簡略地說，「相互」和「互相」的用法幾乎沒有分別，只在「互相」之後不會接名詞。

I don't think there is much difference between the two. You can use them interchangeably.

没区别~~~

Taken literally, they r same.But 相互can be adjective,like 相互的指责/关心.

they are the same, but there are some practical differences: we often use 互相帮助 more than 相互帮助 but 相互理解 = 互相理解 are totally as often used as each other but if you say: 互相帮助，互相理解 is good to make it simple, you can just get rid of '相互' in your dictionary