Is the prayer of one afflicted with obsessive-compulsive disorder valid if performed at home, relying on the fatwa of building upon the most frequent, knowing that he abandates congregational prayer?

If doubt about prayer becomes frequent and turns into a waswas (obsessive whisperings), the cure is to ignore it and pay no attention to it. According to the Maliki school, it is commendable to perform the prostration of forgetfulness ( sujud (definition) al-sahw ) after the taslim (definition) (salutation of peace). The scholar Al-Uthaymeen mentioned three cases regarding doubt about leaving something out: if it is a mere illusion, it does not affect the prayer; if it is frequent—as is the case with those afflicted by waswas—one should not pay attention to it, but rather continue with their prayer. The jurists did not differentiate between a person praying alone or in congregation. The questioner must maintain congregational prayer, for neglecting it exposes one to Allah's wrath, and it also expels waswas.