Oh wow, this is so beautiful and joyous and yet -- so sad, somehow. I think it's not just the last line -- though that's part of it, of course -- but also the combination of present tense (it's all happening now, it's all happening at the same time, it's all happening forever) and the overarching sense of other times, other possibilities, time inexorably passing somewhere just out of sight of this eternal moment.

Er, I have no idea if that's what you intended. But that's how it makes me feel. This is what the word "poignant" was coined for.