Is it permissible for a woman to apply Kuhul(Halal eyeliner) and go out wearing it?
Kuhul is part of a woman`s adornment, and it is forbidden for her to show that to anyone other than a husband , or a Mahram(Unmarriageable kin).
Is it permissible to swear by (Allah ”The Living”)?
Yes, it is permissible because “ The Living “ is one of Allah`s Attributes.
Is the maternal uncle of one`s mother a Maharam?
All perfect praise be to Allah the Lord of The Worlds. May His blessings and peace be upon our Prophet Mohammad and upon all his family and companions.
Mother`s maternal uncle is a mahram. And Allah The Almighty Knows Best.
* In Islam, a mahram is a member of one's family with whom marriage would be considered haram, concealment purdah, or concealment of the body with hijab, is not obligatory; and with whom, if he is an adult male, she may be escorted during a journey, although an escort may not be obligatory.
I can`t afford to get married, what should I do to curb my sexual drives?
You should offer a lot of voluntary fasting, keep busy with useful and permissible acts and make supplication to Allah, The Exalted.