How can you say a person will remain unmarried according to astrology?

Marriage is predicted through 7th house and is conferred by the following.

• Lagna bestowment
• Dasa/Bhukti bestowment
• Transit of favorable planets’ bestowment

Usually if a person’s lagna bestowment is not affected, he/she will get married at right age according to their regional, cultural and socio-economic norms. If lagna’s bestowment is bad for marriage, but dasa/bhukti of planets favorable for marriage is running then it will confer marriage. In worst case, if dasa/bhukti also is unfavorable, during favorable planet’s transit, marriage is conferred.

Only if all three cases fail, a person might remain unmarried. But thirukural says “ Hardwork pays even if God denies”. A person should not lose hope at any point in time.