Project Mothership - The Last Queen of Qorlec, #1

Rose is a nerdy librarian going through a divorce when she is abducted by aliens. When the spacecraft is attacked by the enemies of Queen Nashal, Rose makes it back to Earth freshly impregnated by alien royalty with said enemies on her heels. Now faced with running for her life, she is joined by Zita, a cheerful and beautiful alien marine, who becomes her guardian and protector .