of course marriages last because of no sex, no money, no fire, no this or that...but there's a cost. marriage is a little different according to their priorities. some want financial security and the sex...ah...whenever. My folks actually are married, for 23 years, and have lived in separate homes for about 19 of those years. You talk about sexless! He probably gets laid 4 times a year...if he's lucky. But it works. Is it strange? Sure it is. Not my cup 'o tea. She's into financial security and shopping, he's into having somebody with similar interests. Good buddies who happen to be married. sex isn't a big deal because they have money and with that, things to do and buy.
some want to be friends and do things together, the sex is a forced "marriage thing" that they feel they have to do in order to be called "married". they love being with each other but sex isn't a big part of the equation.
Your question: can a sexless marriage last? Yeah, for two people who agree that sex isn't a big deal. Do I consider my folks marriage one worth keeping? Not for me it wouldn't. That's not my idea of marriage. I wouldn't want a sexless marriage. I'll deliver my end of the marital bargain but I expect the exact same deal on your end. If either party fails, there's gonna be problems.
sex runs hot and cold in most marriages, most of the time because of job pressures, business, kids, or finances. you talk to 10 of your best friends, i'll bet 5 of them don't have sex but once a month. lol...it's true, don't laugh. when you really count up how many times a 30-something or 40-something inserts penis in vagina...i'll bet it is nothing like you thought. but the other five are getting it on at least once a week, minus period time.
you want sex, that's been driven home quite clearly. and your hubby doesn't deliver the goods. the question is squarely on your shoulders: is this the type of marriage you want for the rest of your days? no sex...limited sex...always thinking sex with somebody else? the more you do not concentrate on that single fact, the more it will get out of hand and you lose control of the situation. sex can be a dealbreaker, don't hide from that harsh fact.
if you've told him that this is a biggie, and he will not make you scream with orgasms...don't wait another five years thinking it will get any better. it won't. these are your best years, right now, today. decisions have to be made or you'll be the woman in 2016 who posts on curezone that you're still not getting laid, what should you do? you don't want to be that woman, do you? no. those five years could be the best years of your life, leading to more "best years of your life".