When I properly joined the phandom, it was just at the beginning of the hiatus* and there was a lot of worried posts that they were splitting up/moving apart (remember how every time Dan went quiet for more than a week or so everyone said he was moving out?), and I admit I often let it get to me more than I should have. And then I also had a wobble after BIG, as mentioned above, as a lot of of Dan's "jokes" landed differently for me than they did for a lot of people. So it took me a while, even after they came out, to really believe. And it wasn't just one particular thing or moment, but it was just them continuing to live their lives together despite their careers diverging, really. Just everything they've chosen to share - the holidays, the nights in, just their continuing presence in each others' daily lives. I always thought they were a thing back when they first met, having seen the phan timeline and their very old videos etc, but given what they'd said about it I wasn't, like, 100% positive. Seems almost stupid to say so now, but you know what Dan was like about it. I was in utter shock when he confirmed it in BIG.
But I still wasn't sure about nowadays, as when I joined it was still kind of frowned upon in some places online and "disrespectful" to say they were together. (Still is, in some corners of the internet.) And they, especially Dan, had always been so adamant they weren't an item. (Obviously we know why now, but back then it did confuse me, I admit.) I'd watch things like the final Dan vs Phil for example and think 'how can they *not* be together??', but then convinced myself I was projecting, or it was wishful thinking. Luckily I moved past that.
Oh, but there
was one particular moment that really brought it home for me I guess, and that was Norman.
The fact that Dan has also called him "my fish", that he's properly a joint pet and not just Phil's-fish-that-Dan-helped-out-with, said a lot to me. (I think that's why a lot of people want them to buy a house together or get a dog, aside from the fact it would hopefully make them happy.) So it did take me a little while to get to this point, but here we are.
*I don't think realistically it actually *is* a hiatus any more, that would imply it'll end at some point, but that's what we thought it was at the time