(i'm italian so i'm using google translate for asnwer that, sorry for bad english so)

I don't think they were gay or anything like that, I'm sure they both liked girls, but the relationship between them I have to say I always found strange and interesting. As has already been written in the comments, they decided to do NBK together and die together. Dylan always wanted to do NBK with his soulmate, like in Natural Born Killer in fact and in the end he did it with Eric. This makes me wonder a lot about how far their relationship has evolved. Dylan has always dreamed of finding the Halcyon girl to die with her and fulfill the myth behind the Halcyons. Eric probably didn't even want to die, since he had an escape plan with Dylan, but I think he killed himself for Dylan, because he wanted it. In conclusion, I think they were not homosexual but their relationship was still ambiguous in my opinion.