Your statements about “not attending Church and being a Christian” are contrary to a) The Bible b) The Church Fathers c) The essence of Christianity - which is Theosis through the communal participation in the sacraments and diakonia (which is loving service to one’s neighbor).
Christianity is not a private religion. However, I am guessing you have held to the ideas begun by the Reformers and further pushed by Kierkegaard and Western Individualists that Christianity is a mere matter of choice and it is up to YOU to determine what is True and how to derive Truth from the Bible (or even gnostic texts if you so choose).
The historical, ancient, apostolic, catholic Christianity has always affirmed the Apostolic Tradition (which includes the Scriptures) as the proper interpretation not “what suits you.” It ends up turning into nothing more than religious relativism, and nullifies the whole purpose of the gospel and Christ’s Incarnation.
[i]St. Paul
“Not forsaking the assembling of ourselves together, as the manner of some is; but exhorting one another: and so much the more, as ye see the day approaching.” -Hebrews 10:25
Ignatuis of Antioch
Be not deceived, my brethren: If anyone follows a maker of schism [i.e., is a schismatic], he does not inherit the kingdom of God; if anyone walks in strange doctrine [i.e., is a heretic], he has no part in the Passion [of Christ]. Take care, then, to use one Eucharist, so that whatever you do, you do according to God: For there is one flesh of our Lord Jesus Christ, and one cup in the union of his blood; one altar, as there is one bishop, with the presbytery and my fellow servants, the deacons (Letter to the Philadelphians 3:3-4:1 [A.D. 110]).
Iraneus
In the Church God has placed apostles, prophets, teachers, and every other working of the Spirit, of whom none of those are sharers who do not conform to the Church, but who defraud themselves of life by an evil mind and even worse way of acting. Where the Church is, there is the Spirit of God; where the Spirit of God is, there is the Church and all grace (Against Heresies 3:24:1 [A.D. 189]).
Origen
If someone from this people wants to be saved, let him come into to this house so that he may be able to attain his salvation. . . . Let no one, then, be persuaded otherwise, nor let anyone deceive himself: Outside of this house, that is, outside of the Church, no one is saved; for, if anyone should go out of it, he is guilty of his own death (Homilies on Joshua 3:5 [A.D. 250]).
Cyprian of Carthage
Whoever is separated from the Church and is joined to an adulteress [a schismatic church] is separated from the promises of the Church, nor will he that forsakes the Church of Christ attain to the rewards of Christ. He is an alien, a worldling, and an enemy. He cannot have God for his Father who has not the Church for his mother (The Unity of the Catholic Church 6, 1st ed. [A.D. 251]).
Let them not think that the way of life or salvation exists for them, if they have refused to obey the bishops and priests, since the Lord says in the book of Deuteronomy: “And any man who has the insolence to refuse to listen to the priest or judge, whoever he may be in those days, that man shall die” [Deut. 17:12-13]. And then, indeed, they were killed with the sword . . . but now the proud and insolent are killed with the sword of the Spirit, when they are cast out from the Church. For they cannot live outside, since there is only one house of God, and there can be no salvation for anyone except in the Church (Letters 61[4]:4 [A.D. 253]).
Augustine of Hippo
We believe also in the holy Church, that is, the Catholic Church. For heretics violate the faith itself by a false opinion about God; schismatics, however, withdraw from fraternal love by hostile separations, although they believe the same things we do. Consequently, neither heretics nor schismatics belong to the Catholic Church; not heretics, because the Church loves God; and not schismatics, because the Church loves neighbor (Faith and the Creed 10:21 [A.D. 393]).
Fulgentius of Ruspe
Anyone who receives the sacrament of baptism, whether in the Catholic Church or in a heretical or schismatic one, receives the whole sacrament; but salvation, which is the strength of the sacrament, he will not have, if he has had the sacrament outside the Catholic Church. He must therefore return to the Church, not so that he might receive again the sacrament of baptism, which no one dare repeat in any baptized person, but so that he may receive eternal life in Catholic society, for the obtaining of which no one is suited who, even with the sacrament of baptism, remains estranged from the Catholic Church (The Rule of Faith 43 [A.D. 524]).
[/i]
Of course, you could argue whether or not those statements are true, but that those statements reflect the belief of ancient, catholic Christianity (as contrasted with the many innovations introduced into the faith since the Protestant “Reformation”) there is no reason to doubt.
There is so much ground to cover in explaining all the various implications of the statement that one does not need the Church, but I offer the previous statements merely to present the case that the belief that the Church (as differentiated from goin’ to church, meaning any ol’ church apart from the apostolic, catholic Church) is not necessary to being a Christian has no grounds in what Christians of the first five hundred years believed.
All sources are saints who in their day and even to today were a) apostles b) disciples of apostles c) prominent bishops d) respected theologians e) some combination of the above.