Hi Laura, it’s not the first time I see or hear someone say they can’t fully express themselves in English. I think what helped me to develop the habit of thinking in a language without translating in my mind to/from my native language, is immersion and exposure to the languages. What I mean by immersion is that I’ve had various opportunities to use those foreign languages in real life situations, like volunteer workcamps, traveling with someone who doesn’t speak my native language, couchsurfing, living and working abroad — when I had to live, work, go to bed and get up speaking English, it had a huge positive impact on the way I perceived English, it just stopped being foreign for me and speaking the language all day long made it easy to think in English straight away. You’ve been immersed in the language too, that’s great, but it takes time to actually stop perceiving a language as strange and become comfortable living your life in it. Another thing, you don’t necessarily have to live in an English-speaking country to become more confident in the language. There are millions of non-native English speakers out there who speak the language very well and who you can learn from. The first time I went to Germany to volunteer in an international workcamp so English was the language we all communicated in, and I remember my attitude to it and my speaking skills improved a great deal though there was no native English speaker in our workcamp.
When I mentioned exposure, I meant surround yourself with English listening, reading, watching, commenting on the content of your interest. It’s so easy to do if you follow someone on social media who talks/writes in English about whatever you’re interested in, be it solo traveling, vegan recipes, bio cosmetics, you name it. The effect will multiply if you not only read, watch or listen to the content but also engage in it by leaving your comment, asking a question, or commenting on on somebody else’s reply.
Hope that helps.