Same sex relationships in swtor is a lot different than the inclusion of the Cather as a playable species. BioWare did say that current companions would not be same sex partners and that to enable it they'd have to come up with new companions for players in later expansions.
Also, the announcement of Makeb was back during E3 2012... so with it's spring 2013 release, they would have a year of work put into it at least. That and there's still quite a few months to go till that time period. They've said several times over the last few months that the Makeb team have been working on the project continuously, so the real question ow is, how big is Makeb really going to be? We get a 5 level cap increase along with it so is the planet (assuming you play through it with a single class) going to be meaty enough to last 5 levels without the use of exp boosters?