EVER.

Let's look at the evidence:

Twilight basically owns him - he is eternally in servitude to her as she is the one that hatched him and so basically she is his "mom".

He has a crush on a being not of his own race. I also speculate whether this is a legit crush or because she represents gems, the things he loves - but even if it is an actual romance, it's doomed and she's basically friendzoned him and he's just desperate for any attention from her.

Nobody wants spike to grow up because if he does he basically won't fit in equestria anymore and will be forced to leave. It's also been hinted that as the dragons age they lose intelligence, and sometimes the ability to speak, as evidenced in spike when his hoard grows, and thus, so did he. Each time he has been made to be bigger he's been portrayed as lacking intelligence.

So spike is doomed to be alone, get dumber, angrier, and just generally more dragony.

And with absolutely no female dragons shown whatsoever in the series so far - he might even die alone.

The creators don't really even seem to want to give him much of a chance either - he's seen as the butt of jokes half the time, or just not taken seriously.

Poor spike.

oh he also is princess celestia's cell phone service.