Wow, that is the problem with this site. You have to weed out the bad advice to get to the good.
Anyway, I am going through exactly what you are going through. We started solids at six months and that is precisely when Connor STOPPED sleeping through the night (don't tell me it is teething, he's been teething since he was three months old and sleeping through the night from 8weeks to 6months). After talking to MANY other moms on the subject, it is quite common for this to happen. I believe it corresponds to baby realizing that they and mom aren't one "being", and they realize that mom does leave and they think that mom is never coming back...at least it makes sense to me.
We've been given all the same advice as you have here, including add solids, take away solids, feed more during the day, etc etc. But it is only so easy to dispense this advice if they have never been in your shoes.
What we have done is we have stopped feeding solids (we'll start up again soon, at eight months) because he always was really upset in an evening that we fed them. I also do try to feed more during the day which sometimes only happens if I swaddle him, because he is sooo distracted during nursing sessions, he spends more time looking around than eating and I spend more time trying to keep him from pinching, pushing, grabbing my nose and hair, etc...I bought a nursing necklace from http://www.etsy.com/shop.php?user_id=5079958 which has helped a little with the distractedness. Needless to say, with a distracted baby it can be impossible for them to get all of their calories during the day so a night feed or two is necessary (and completely normal!!) regardless of the fact that baby slept through the night for such a long time.
Along with everything else, we also have started cosleeping. If you are worried about your husband being a deep sleeper, all the cosleeping guidelines say baby should be between you and the edge of the bed (with a suitable rail of some sort on the edge of the bed). I definitely recommend nursing while laying down, I have found I really don't have to do much but lift my shirt and pop the nipple in his mouth. He falls asleep once he gets his fill and if I'm somewhat awake I'll replace my nipple with a pacifier.
We are no where near sleeping through the night again (HAHAHA to the person who said it would take a week) but by doing the above I've been able to make it so he is only waking up two, sometimes three times a night.
I think the best advice I was given was to do whatever it took to get the most amount of sleep for myself. Don't listen to the people who will say "Oh, if you cosleep and nurse to sleep now, they'll constantly be dependent on you to fall asleep!" Here's a newsflash. We gave birth to newborns, not five year olds, they ARE dependent on us for a lot, it makes sense!
Good luck momma :)