If you ask linguists, English is one of the hardest languages to learn. It has many intricacies that don't make sense to people who speak other languages.
But once you learn the language, you then need to understand that there are tons of different English dialects. Basically, it only gets more difficult from there. To give you a bit of insight into these accents, one guy gave 35 of them a go.
If you're a native English speaker, why not try to master a few of these? If you're still learning English, don't give up! We're all pulling for you.