No matter who you choose, they will likely raise your rates every year even with no claims and will likely raise your rates very fast after you have claims. At some point, you might not be able to afford the insurance payments.
Even if they offer the dependent visa, you might want to apply on your own so that if one passes, the other is still eligible on their own to stay with no extra steps. Or maybe the dependent gets grace period to sort out things?? But you might not be in the frame of mind to deal with visas in that event so better to just be here on your own visa.