Does the emission of semen merely by thinking about marriage or men necessitate repeated ghusl? And does excessive worrying about madhy, for fear of it invalidating one's ablution during prayer, cause it to be discharged, thereby leading to a dislike of prayer and avoidance of reading the Qur'an?

One must differentiate between manī (sperm/seminal fluid) and madhī (pre-seminal fluid) due to the difference in their rulings. Manī is pure and necessitates ghusl (ritual bath). If its discharge is continuous, it is considered sils al-manī (incontinence of seminal fluid), and prayers can be performed with it after performing wudu' (ablution). As for madhī, it is impure (najis) and necessitates washing whatever it has touched, in addition to performing wudu'. If its discharge is continuous, prayers can be performed with it after purification, without harm. Patience and submission to Allah's decree are advised, as there is goodness in that.