Sorry it took a bit to get to this, @suntiger745!
In the short of it, he met a druidess at a bonfire bash well back in BFA and worked with her adoptive daughter for a while when she was in his classes. Through various misadventures and tribulations for the next six years, they both refused to acknowledge or admit any developing feelings whatsoever for several years after until Almaeth was almost killed which made him realize there were a lot of things he would regret if they went unsaid. They've been together ever since. It wasn't anything too dramatic or spectacular, just a very slow, very long build up over a long time.
She's a lot more outgoing and risk taking than he is which pulls him out of his comfort zone. She's been extremely healthy for him.
They have a small farm together in Elwynn currently, and right now they're in Eversong helping out on their own volition.
Almaeth belongs to @pridemother-scribbles