Is the fear of not remarrying after rejecting a good suitor a sign of having a bad opinion of Allah? And does the rejection due to religious conditions and a lack of readiness for marriage at that time necessitate Allah’s wrath, or is what happened simply divine decree?

It is permissible to reject a suitor who possesses religiosity and good character if some other desired qualities are not present, for the encouragement to accept him is not an obligation but a recommendation. Allah does not punish for leaving a recommended act, and what befell you is by Allah’s decree. Do not dwell on the past, and say: "Qaddar Allahu wa ma sha'a fa'al" (Allah has decreed and what He willed He did). Belief in divine decree is a comfort for the soul. Fear of suitors not coming is not a sign of ill-faith in Allah, unless it leads to despair of His mercy. You should look forward to the future, supplicate frequently, and have a good opinion of Allah. Marriage is sustenance, and if a woman does not find someone with many desired qualities, she should be content with someone who is generally religious.