Is it permissible to divorce a wife who faints during intercourse, making marital life difficult, and what are the implications in terms of alimony, deferred dower, and expenses if a divorce occurs?

You bear no sin for divorcing your wife for the aforementioned reason; for divorce, if done out of need, is permissible. If you divorce her, then she is entitled to her full mahr (dowry), and to nafaqa (maintenance) for the duration of her iddah (definition) (waiting period), and to mut'ah (compensatory gift) according to some scholars. The nafaqa and mut'ah vary according to the husband's financial situation, and their estimation is left to the discretion of the judge in case of dispute. As for the maintenance of the young daughter, it is incumbent upon you in all circumstances, as long as the daughter is in need of maintenance.