Hi @Kox
No, you do not lose the permit after a divorce. It is a permit of permanent residency. The only case in which you can lose the permit is if you stay outside Germany for over two years.
You can read this yourself in the law which covers this called 'Freizügigkeitsgesetz'. Paragraph 4a covers Daueraufenthaltsrecht and section 7 in it mentions this rule about losing thepermit after an absence of two years:
https://***-gesetze--im--internet-de.translate.goog/freiz_gg_eu_2004/__4a.html?_x_tr_sl=de&_x_tr_tl=en&_x_tr_hl=en&_x_tr_pto=wapp
Best,
Éanna