Some of the replies in this thread, especially the first few, seemed like they didn't read or understand your message. Those people need to re-read your original post: you depend on this woman for financial support, a home, etc.
Now...listen to me carefully as I'll give you a different point of view...
You have 3 situations here on your hand:
1. Wife's mental health is degrading
2. Your financial stability could potentially be in uncertain times up ahead; and
3. Your sexual "needs" are not being met
So hear me out...
For number 3 - what happens when you get your satisfaction? You get some action, you release, and...done. All that energy is up and gone away. For self-satisfaction.
Another way to view this is possibly to try sexual transmutation.
This is where you save your sexual energy and direct it towards a bigger cause, a goal, something greater than what you can achieve on your own.
Think about it - you have a challenge on hand right now, it's probably only going to get more challenging unless you get super-lucky and find (another) sugar-mama type of deal. You may actually be able to pull that off with transmutation. Or, you may be able to accomplish other (bigger) goals that result in much much more meaningful outcomes than busting a nut to feel satisfied.
Take a good look at yourself, look back at any point and time in life you had full sexual satisfaction. What purpose did it serve? How far did it propel you?
I personally have "done it all" as far as a male/female combo can go. Any and all sexual acts. I've had the most aggressive females in my bedroom who not only "allowed" me to do as I wished, they demanded that I do. Front door, back door, up stairs, down stairs, sit on their face, and on and on and on. Listen buddy, none of it resulted in any real "satisfaction". If anything, I always wanted more. I think it's built into us as men to want more.
I've had 3 rounds of sexual transmutation in my life. 2 times were with complete abstinence, and once was with sexual activity without orgasm (you save it). All 3 times resulted in amazing energy, confidence, drive, focus, goal oriented, better health, and on and on. I'm on round 4 right now going on my 2nd week, it's just starting - this round I plan to go 3 months - then a 1 week break - and right back into it.
Good luck buddy. Don't knock it 'till you try it.
Read up!