You asked "Is it too late to get into startup mode?", I don't think so. I think that you might want to discuss this with your wife and get her input into this decision too. Marital acrimony along with the stresses of a startup might take its toll on both of these things, and that would be regrettable.

In any case, as far as getting into "startup mode" it might help if you had an offering that you really believed in. Something to wow the world with. An idea for a product or service that is compelling to you and to others (a lot of others). Something your wife would believe in too.