The most important part is 'love' (the emotional component of a relationship), along with something that is of secondary importance, which is 'sex' (OR to say it nicely, physical expression of love!)
So, gay, lesbian, bisexual, homo, hetero, single, couple, whatever, do not really matter so long as two people love each other!!!
If the world can be the one I have described above, the world then becomes much more lovable since tolerance is the common denominator for all!