I have to respectfully contest comment below that it is normal for children not to sleep through the night until they are 2-3 years old. I have two children - 2 years old and 8 months old. The 2-year-old sleeps 10-11 hours a night and the 8-month-old sleeps 12 hours a night - no waking - and she's on the verge of getting her first tooth. Both children began sleeping long, 12-hours stretchs at night around 4 months old.
I am a HUGE fan of the book "Healthy Sleep Habits, Happy Child" written by a doctor who has done sleep research on children. It talks about what the biological sleep needs are of children at different ages, their sleep cycles, and how what we do as parents greatly affects that.
I'm not sure what to do in your situation, but the book offers a whole lot of troubleshooting advice. Go to the library or book store and at least take a look at it.
I guess from what I've learned from the book, I'd advise you to have white noise like a fan going, the room dark, a consistent/soothing night time routine, a regular nap schedule during the day, and let the baby fuss and have the opportunity to put himself back to sleep during the night. If I were you I would put in ear plugs and then you'd only be responding to the baby when he is actually crying (which I can definitely hear even with ear plugs in).
Anyway, I hope that helps and that you guys can get some much needed rest before your baby is two years old!
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