Menstrual wife can sit on the mat beside Husband

Narrated Maimuna

(the wife of the Prophet) During my menses, I never prayed, but used to sit on the mat beside the mosque of Allah's Messenger (ﷺ). He used to offer the prayer on his sheet and in prostration some of his clothes used to touch me."

Sahih Al-Bukhari 333

In-Book : Book 6, Hadith 37