The terms hetero and homo refer to gender, not sex. So nothing has changed and whatever attracted you to him is what attracted you. If that’s gender-expression, and that gender expression has changed, and you’re no longer attracted, then hetero is the term for that. If it was, but you were attracted to his masculinity, then homo is appropriate. If you were attracted to his feminity, but also like his masculinity, then bi is appropriate and if his gender never played a part then pan is appropriate.

That being said, the other person doesn’t really define your label. Just call yourself what you like. It’s completely okay to like someone for one set of reasons, and then stay with them because you grew closer and found a bunch of other reasons, and are now in love and have a life together.