It's a colleague of DH's. I've never met the colleague or his partner. I've never met any of DH's colleagues.
DH feels he should go. I agree. I've offered to go with him. But the logistics are a bit of a shitshow. Its easier if I don't go. I'd prefer not to go.
How weird is it if DH shows up solo?
Edited to add: We've both been invited to day and evening bits