Yes, you can still make progress learning Dutch with memory issues from PTSD, but you need to adapt your approach to leverage your grammar strengths and work around vocabulary retention difficulties. Focus on using context-rich input and spaced repetition systems (SRS) in a low-pressure way, and accept that progress will be slower and require different strategies than typical learners.

First, lean into your grammar intuition. Since grammar clicks for you, prioritize understanding sentence structure and word order through reading and listening to simple content like children's books or news sites for learners (e.g., Jeugdjournaal). Grammar provides a scaffold that makes vocabulary more meaningful and easier to recall when you encounter it in context.

For vocabulary, avoid brute-force memorization. Instead, use SRS apps like Anki or Memrise, but with custom settings: limit new cards per day to 5-10, use images or example sentences instead of translations, and review only once daily to avoid overwhelm. Pair this with extensive reading and listening where you encounter the same words repeatedly in natural contexts, which strengthens retention without conscious effort. Consider using graded readers or podcasts for learners (e.g., "Zeg het in het Nederlands") that repeat core vocabulary.

Acknowledge tradeoffs: you may never have a large active vocabulary, but you can become highly functional with a smaller set of high-frequency words used accurately. Accept that some words will never stick, and that's okay. Focus on communication strategies like paraphrasing or asking for clarification.

Concrete next steps: (1) Set a realistic goal, like understanding 80% of a simple news article, not fluency. (2) Use SRS with strict daily limits and only review after sleeping. (3) Spend 20 minutes daily on grammar exercises (e.g., conjugations, word order) to reinforce your strength. (4) Join a low-stakes conversation group where you can practice without pressure. (5) Track your progress by noting how many words you recognize in a short text each week, not by how many you can recall from memory.

Finally, be kind to yourself. Your brain has been through trauma, and language learning is a cognitive workout. Celebrate small wins, like understanding a sentence without translation, and consider consulting a speech-language therapist who specializes in acquired memory issues for personalized strategies.