Welcome to GamerWidow.
Yea, you do have a real problem on your hands...after seeing the 4 posts you and Gina made, I can honestly say you need to leave him. Gaming is not wrong, but since we're all here about addictive gaming...yes, it does destroy lives. Working, taking care of 4 kids and a husband who doesn't give a shit about anything apart from his gaming and taking care of the house is a big thing.
As far as you saying why people stay and put up even after so much...well, it's because the people who are in a relationship think of it as a relationship. They want to make the time, effort and so on to be in a relationship. If 2 people in a relationship have a fight, do they adjust with each other and grow closer, or they file a divorce/separate from each other at the smallest argument?
But yes, after so many years of it, why do people put up? Guess, as Gina said, the thing of too far in to back out does make people think so many times. A gaming addict, like your husbands, or me gets too far in a game to back out. Same goes for alcoholism, gambling, sexual addictions and so on. People feel it is right, the mind keeps reinforcing the same thing over and over and repetition gets it solidly founded to the extent that breaking it becomes an almost impossible job unless they themselves decide to change.
Also, as I said above, people want to be in a relationship, so they put up with all they can endure. Some give up, some give in, some give it all they got, but they do it...because it means something to them. You both are wives to whom a relationship matters. You love your husbands, your life, your kids and that's why you want to maintain it, which is why you put up.
But slowly, out of a lack of something (in your case, the lack of your husbands being there with, for and by you in a relationship), the person and the relationship slowly start dying. Maintaining a relationship has become a routine, so you do it hoping things will improve. But they don't. Things deteriorate and start falling apart. Yet people put up, because of that one small thing called hope. The thinking that, 'Maybe someday, things will improve.'...thinking that it'll all become all right.
That is why people put up, endure and do all they can. But things don't change...yes you do deserve better. I don't want to sound harsh here...but it's because you love something/somebody, that you have to make the hard decisions. You love yourself, your kids and your life. You even love your husbands, just not their absence. But it's because you love all this, hard decisions need to be made. So, not wanting to sound harsh, but leaving might be the only option you have. End of the line for nuisance.
You get only one life...so, make the most of it. Life's not meant to be wasted. It's priceless...and just one. Don't waste it.
Hope you find a better way of things.
"Everything is relative and situational...all depends on your choices" - EiRaSAdoyC.