I think you're not being selfish. Putting your baby as your foremost priority, even at the lowest of your health, is actually a selfless act. Even if you are struggling right now, you still choose to give your baby the best nutrition there is. So please do yourself a favor, stop thinking you're a selfish. You are indeed a good mom.
Just tell your in laws that you can handle your situation, and be firm with what you want. However, don't lose respect because they're still your husband's parents. Good luck and I hope you recover soon for your bub!
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