As a non-native speaker of English, I have been feeling awkward about it. My pronunciation carries a heavy Japanese accent and my listening skills are far from perfect. I am a very slow reader of English. However, when it comes to writing English, there is a silver lining. Unless you are participating a real-time chatting, you are not required to respond to something quickly when you write it. You can stop to think for a while. You can modify your sentences after drafting swiftly.
I am aware that my grammar is not perfect. I do know that I keep making small mistakes regarding choices of particles and singular/plural. Writing nouns is the most difficult part of English. The distinction between countable and uncountable nouns is just terrifying.
Choice of words is not the only problem. Even problematic is choice of phrases or syntax. There are some very English-like syntaxes. (Sorry, I can't come up with a good example) Not only words but also syntaxes are very different between Japanese (my mother tongue) and English. It is very difficult for me to compose natural sentences characteristic of English.
After a long reflection, however, I came to a conclusion that it does not really matter. The most important thing is to have people understood my ideas. As long as there exists a context, my subtle grammatical errors or unnatural syntaxes in English do not prevent people from understanding what I want to mean. What a great relief am I given if I think this way!
In a way, this is the invention of a new language, my own English. It is not exactly the same as what typical American people speak, but still understandable to them. I can express my ideas with that tool. Let's not worry too much about superficial things such as grammar and wordings. Let's focus on the thoughts that I want to convey.
My English is already good enough to express anything in the world. Let's stop worrying and start telling something more interesting. Probably, my writing skills also grow gradually. But it doesn't really matter. The most important thing is what you say, not how you say.