Praise be to Allah (The Glorified and Exalted).
1) Your argument against the jinn that has possessed you is very simple,
"The religion of Islam correctly speaks about your existence and the abilities given to you by Allah (The Glorified and Exalted), and the matter concerning your creation is as mentioned in the religion of Islam. This knowledge could have only come from the Creator, because the jinn are hidden from mankind. Therefore, Islam is the truth." Whereas the majority of other religions do not accept the existence of the jinn race. There are some other religions that do believe in the existence of evil spirits, but they are nowhere near accuracy in describing the purpose of their creation and their abilities and relations to mankind. Therefore, Islam is the truth because it accurately describes the creation of the jinn race and this knowledge could have only come from the Creator.
Curing the Possessed:
(1) The followig Dua (Supplication) can be recited by the one who is suffering from some calamity:
Sa’d said:
The Messenger of Allah (peace and blessings of Allah be upon him) said, “The call of Dhoo’l-Noon [Yunus], which he recited when he was in the belly of the fish [whale],
‘La ilaaha illa anta subhaanaka innee kuntu min al-daalimeen.’ There is no Muslim who recites this in any situation, but Allah will respond to him.” [al-Tirmidhi no. 3427; classed as saheeh in Saheeh al-Jaami’, 3383]
(2) The Prophet (peace and blessings of Allah be upon him) said:
“There is no-one who is afflicted by distress and grief, and says:
‘Allaahumma inni ‘abduka ibn ‘abdika ibn amatija naasyati bi yadika, maada fiyya hukmuka, ‘adlun fiyya qadaa’uka. As’aluka bi kulli ismin huwa laka sammayta bihi nafsaka aw anzaltahu fi kitaabika aw ‘allamtahu ahadan min khalqika aw ista’tharta bihi fi ‘ilm il-ghayb ‘indaka an taj’al al-Qur’aana rabee’ qalbi wa noor sadri wa jalaa’ huzni wa dhihaab hammi (O Allah, I am Your slave, son of Your slave, son of Your maidservant; my forelock is in Your hand, Your command over me is forever executed and Your decree over me is just. I ask You by every name belonging to You which You have named Yourself with, or revealed in Your Book, or You taught to any of Your creation, or You have preserved in the knowledge of the Unseen with You, that You make the Qur’an the life of my heart and the light of my breast, and a departure for my sorrow and a release for my anxiety),’ but Allah will take away his distress and grief, and replace it with joy.” He was asked: “O Messenger of Allah, should we learn this?” He said: “Of course; everyone who hears it should learn it.”
(3) In order to remain protected from possession, the Muslim should pray all obligatory prayers and attempt to keep wudu (state of purity, abultion) throughout the day as much as possible. Reciting Qur’anic Chapters 1, 2, 113, and 114 frequently along with Ayat al-Kursi everyday is also a great benefit.
Possession can be cured by reciting Chapters 1, 2, 113, and 114 of the Qur’an over the possessed. This should be done by the individual or someone who has strong faith and it should be repeated several times, in that the Chapters 1, 112, 113, 114, and Ayat al-Kursi (2:255) should be said several times in one sitting and blown (i.e. "kuffed") over the possessed.
(4) The Prophet (peace and blessings of Allah be upon him) used to treat his companions:
“Allaahumma Rabb al-naas, adhhib il-ba’s, washfi anta al-Shaafi laa shifaa’a illa shifaa’uka shifaa’an laa yughaadir saqaman (O Allah, Lord of mankind, remove the harm and heal him, for You are the Healer and there is no healing except Your healing, with a healing which does not leave any disease behind).”
(5) There is also the following Dua of Angel Jabriel (Gabriel) (peace be upon him) to cure illness:
“Bismillaah urqeeka min kulli shay’in yu’dheeka, wa min sharri kulli nafsin aw ‘aynin haasid Allah yashfeek, bismillaah urqeek (In the name of Allah I perform ruqyah for you, from every thing that is harming you, from the evil of every soul or envious eye may Allah heal you, in the name of Allah I perform ruqyah for you).”
(6) In order to cure black magic, the following can also be done: some have successfully used seven lotus-tree leaves. The leaves should be crushed, then mixed with water, enough for taking a bath. The following verses from the Qur’an are then recited: Ayat al-Kursi (2:255), Surah Al-Kafiroon (109), Surahs 112, 113, 114; the verses which mention magic, which are: in Surah Al-Baqarah (2:102), Al-A’raf (3:117-119), Yunus (10:79-82), and Taha (20:65-69). The possessed person drinks some of the water, and the rest is used to give him a bath [Shaykh ‘Abd al-Rahman ibn Hasan (may Allah have mercy on him) in Fath al-Majeed].
(7)
“A’oodhu bi kalimaat-illaah il-taammati min sharri ma khalaqa (I seek refuge in the perfect words of Allah from the evil of that which He has created).”
(8)
“A’oodhu bi kalimaat-illaah il-taammati min ghadabihi wa ‘iqaabihi, wa min sharri ‘ibaadihi wa min hamazaat al-shayaateeni wa an yahduroon (I seek refuge in the perfect words of Allah from His wrath and punishment, from the evil of His slaves and from the evil promptings of the shaytaan and from their presence).”
(9) The Believer can also recite the following verse of the Qur’an,
“Hasbi Allaahu laa ilaaha illa huwa, ‘alayhi tawakkaltu wa huwa Rabb ul-‘arsh il-‘azeem (Allah is sufficient for me. None has the right to be worshipped but He, in Him I put my trust and He is the Lord of the Mighty Throne)” [9:129].
(10) The parent can also recite the following for their children, narrated that the Prophet (peace and blessings of Allah be upon him) used to seek refuge for al-Hasan and al-Husayn [his grandchildren] and say,
“U’eed-hu-kuma bi kalimaat Allaah al-taammati min kulli shaytaanin wa haam-mah wa min kulli ‘aynin laam-mah (I seek refuge for you both in the perfect words of Allah, from every devil and every poisonous reptile, and from every evil eye)” [al-Tirmidhi no. 2060; Abu Dawud no. 4737].
(11) The last two verses of Surat Al-Baqarah (Chapter 2), will suffice a Believer.
Abu Mas’ood al-Badri (may Allah be pleased with him) said:
The Messenger of Allah (peace and blessings of Allah be upon him) said, “The last two ayahs of Surat al-Baqarah – whoever recites them at night, they will be sufficient for him.” [al-Bukhari no. 3786; Muslim no. 807]
(12) If someone is afflicted with the evil eye, then they must get the envier to perform wudu and pour the water upon the afflicted person.
‘Aisha (may Allah be pleased with her) said:
The person who had put the evil eye on another would be ordered to do wudu, then the person who had been afflicted would wash himself (with that water). [Narrated Abu Dawud; This was classed as authentic by al-Albaani in Saheeh Abi Dawud]
The following fatwa also makes mention of treating the evil eye: “If it is known or suspected that a person has been afflicted by the evil eye, then the one who put the evil eye on him should be ordered to wash himself for his brother. So a vessel of water should be brought, and he should put his hand in it, rinse out his mouth into the vessel. Then he should wash his face in the vessel, then put his left hand into the vessel and wash his right knee, then put his right hand in the vessel and wash his left knee. Then he should wash inside his garment. Then the water should be poured over the head of the one on whom he put the evil eye, pouring it from behind in one go. Then he will be healed, by Allah’s leave” [Fatwa al-Lajnah al-Daa’imah li’l-Buhooth al-‘Ilmiyyah wa’l-Ifta, 1/186]
You may recite any of what is mentioned above. Let us know what happens after attempting all of the above several times.
*Also see the posts: The Jinn Race and Proving Islam
http://www.turntoislam.com/forum/showthread.php?t=41106
http://www.turntoislam.com/forum/showthread.php?t=40837
And Allah (The Glorified and Exalted) Knows Best.