I really felt for you when you said you could never hope to pass. Nature has seen fit to gift me with an extreme variation on female anatomy (boobs like watermelons). I hope to get top surgery eventually, but for now, I'm stuck with them. I am changing what I'm able to change, however. I have an appointment to get my hair cut, and I plan to get a masculine style. I'm ditching the purse, and am looking into getting more gender-appropriate glasses. I've been trying to find a place that makes custom binders, since the off-the-rack ones are all too small. I found a couple of places online that make custom-order male clothes. (I can't wear ready-made men's clothing either, because it's just hopeless.) This is going to involve a lot of time and money, but I'm willing to invest those things. My only other choice is to do what I've always done--hide my head in the sand and hope that the dysphoria will just evaporate one day. I don't see it happening.
Also, since your weight is so high, have you considered looking into bariatric surgery? Many insurances will cover it. More very heavy people take the excess weight off and keep it off with surgery than with diet and exercise alone. Just a suggestion.
I don't know what to tell you about your wife, I'm afraid. I'm very sorry that she's not more supportive. The married users of this site can probably steer you better than I can.