The word bastard has 2 connotations in the English language. One is the illegitimate meaning and the other one is the vernacular and derogatory meaning.
The normal meaning from my little pocket dictionary is “child born of unmarried parents”.
On a literal translation therefore, even if you said this, it cannot be derogatory.
However the phrase retard is without a doubt derogatory.
I don’t know how you complain to Facebook to get this removed if they will remove it but it’s worthwhile trying.
My suggestion would be to get a solicitor to write threatening an application to court for an injunction to make her remove the post and substantial legal costs against her if she doesn’t remove it voluntarily.
Hopefully, (usually the case) these matters resolve without the need for court proceedings which could be potentially expensive.
Can I clarify anything else for you?
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