What can replace "The" church for Christians?

For most Christians in recorded history (although not in the Gospels) being-a-Christian is the same thing as being an observant member of "The" church. 

But, of course, the identity of that The as it is applied to church; has varied in often incompatible and hostile - even lethal, and frequently evil - ways; since very early in recorded church history. 

Since the minds of Men and (therefore) society have both changed, Christians now choose The church for themselves, and choose which faction within that The which they are to be observant to. 

However; Christians then typically forget or deny that their own choices are rooted in personal assumptions - and usually pretend (for they are being untruthful) that their-"The" church is objectively, and evidentially, the-"The" church. 

So; for Men here-and-now churches cannot be, therefore they are not, what they were. 

Churches cannot be "The"; and cannot provide what they once (often) provided - and especially no church can be regarded as The in that way which was natural and spontaneous for so many centuries.  

What, then, can - or should - replace what The church once used to be? 

The first answer is nothing, there can be no replacement; because churches are all institutions, and all institutions are changed. 

All institutions are substantially and motivationally totalitarian-bureaucracy-assimilated; and have lost their distinctive purposes and the life-meanings that flowed from them - churches are now fundamentally, as well as in-practice, this-worldly. 

But perhaps what the churches used-to provide can be divided between spiritual and social? 

If so, the spiritual provision used to be external; mediated by symbolic, language and ritual; quasi-objective; and to-be-obeyed. 

This is exactly what has gone, and therefore this cannot be replaced for modern minds. At least; it cannot be replaced effectively and with sufficient motivational power. 

Churches as spiritual sources are self-subverted, hence relatively ineffectual - and so are church people. 

Instead, spiritual sustenance needs to come from direct participation with the divine - and all Christians therefore need to become mystics, in a certain sense. All Christians need themselves to communicate with (of know) the divine and the Beings of this world. All Christians need to be clear that their ultimate evaluations Just Are individual - and should work on making these as valid as possible. 

What of the social aspects of church? 

The social side of what churches once were cannot be replaced either; because society has transformed in its structures, laws, traditions, evaluations - and so forth. There is no longer an old-style church niche. 

Furthermore, with people as they now are; social support, inspiration etc is not, and cannot be, generically prescribed. First because generic provision is not wanted, not needed, and indeed actively abhorrent. 

But also because social provision (by whatever is The chosen-church) is so scanty, incomplete, crude, intermittent, insufficiently-sustaining... and basically unsatisfactory. 

We are long-since at a point (and this can, surely, only increase) where each individual Christian needs to seek for the social support he needs - search for wherever he can find it; in whatever form he can tolerate; and social support provides what he most needs; and in whatever way works-best for himself.

(Although that "best" is itself almost sure to be both short-term and insufficient.)

My conclusion is that the model of "Christianity" based upon The church is either dead and gone, or already-feeble, mis-matched, and dying.  

The alternatives to The church are not replacements but substitutes; and all substitutes rely upon an acknowledgement of the validity (as well as the necessity) of individual discernment, choice and validation. 

As see this as a plain fact - and IMO Christians ought to be honest enough to acknowledge plain facts.