How can members of the zodiac tanggal each other?(may contain spoilers)

well sometime the two r really in love. they feel like they r distantly related when they r under the curse. but when the curse is broken they feel entirely different and happy for each other.

I think somewhere in the komik jepang they say something about the whole 'cousin' thing (I'm not sure where). But I believe they berkata that their not sure exactly how they are related but since they all have the same last name they must be somehow, hence why they say their 'cousins' (and their bloodlines are so far apart that it doesn't really matter if they date. Remember it's a HUGE family). It's like if anda know someone anda has the same last name as anda but none of your atau their relatives know each. And none of them look like each other either. I also don't think they have to tanggal another zodiac member just because of the curse (ex: Yuki and Machi, Kyo and Tohru, Kureno and Arisa, Hatori and Mayako, Ritsu and Mitsuru, Ayame and Mine, the sebelumnya cat). Haru and Rin, and Hiro and Kisa are just in cinta with each other simple as that. Hope this helps! :)