@Michi *******
I'm not sure that can be true. The e-visa itself is valid for 5 years. The 180 day entries begin in validity when you enter the country. I've entered with and without my husband as he has with and without me and we've always been stamped in, no questions asked. There isn't really a way they can require spouses to travel together for everything. We don't have kids as dependents, though, so I don't know if that changes anything.