I was in a similar situation (not exactly the same) around this time an year ago, I'd moved to the
US for work and came back to India to get married.
My wife and I wanted to visit the UK and Ireland for our honeymoon. We'd applied for UK visas separately as single individuals, didn't mention marriage or honeymoon in the application. I'd applied in
NY whereas my wife had done so in
Bangalore. Since both of us work, we had adequate financial means on our own it wasn't a problem and we got our visas.
The visit thereafter was smooth too.
I'd recommend you do the same if your circumstances are similar, if however your wife isn't working then I'd recommend waiting till the wedding and applying together after that.
Another side note (I don't recomment this course of action but you should know about this) : Since this is schengen if you feel one country's requirements are more stringent than another then you could apply for one which has easier requirements. I know a friend and his wife who visited Italy and even when they were applying from
NY they had to go for an in person interview, went smoothly for them. I'm thinking
Spain can do with tourists, god knows their economy needs it.