This is a hard thing to see our child go through. It's not only you though. So don't feel bad.
If he is getting up every hour, and it seems like you've tried everything.... well I'm not real sure. But, which ever method you try, you have to try it for several days... to see if the routine will work and you have to give the baby time to adjust to it. Don't do a "new" routine every day... that is too much confusion and inconsistency for them. Babies and children learn by repetition... and "knowing" what comes next.
He is also 7 months... is he rolling over yet on his own? Many times, by this age, putting them on their tummy can help them to sleep better. But this is debatable, in light of SIDS. Personally, my son sleeps better on his tummy or on his side. When we got older, he just did this himself.
Also, since you are nursing, you want to make extra sure that he is getting enough intake. Meaning, is he latching on appropriately and suckling properly? The reason I ask is, MANY times, it may seem like just because baby is at the breast, it's assumed they are suckling and drinking. But in actuality, they may not be a good nurser or not have adequate suckling to where is is productive. IF this is the case, then, they are not getting in enough intake and may actually be hungry. I have seen this many times with friends.... their baby cries a lot and does not sleep well... but after seeing a Lactation consultant, it was found that their baby was not actually nursing well, thus, not getting in enough milk/calories. One Mom I know, even had to supplement with formula, and make sure her baby was taking it in. After doing this, their baby started to sleep... and not wake up all night, nor cry all night. The baby was basically starving. This was not until about 5 months old, that they figured this out.
Maybe your baby is just hungry and not getting in enough intake? Do you know how many ounces he drinks per sitting?
Also, each baby is different, with different personalities and temperaments. My oldest for example, was a very light sleeper and she is "noise" sensitive, even to this day. As a baby, it was not easy getting her to nap or sleep at night. Any noise would wake her up. My son on the other hand, has no problem sleeping and takes to his routine very well.
Also though... does anyone, you or Hubby, "snore" or move around a lot at night when sleeping? The reason I ask is, this can wake up a baby. Think about it.. .even as adults, snoring can be disturbing for the spouse, interrupting one's slumber. You might what to think about this too. Since you are co-sleeping.... maybe try putting him to bed in a crib or something.
I have not been big in doing the CIO method for my own kids. But here and there I did try. But it didn't work. What I found was best, is just keeping up a consistent routine, same sleep times, same sleeping place, same everything EVERYDAY.
Also, maybe he is just over-tired. At this age, they typically take 2 naps a day, morning and afternoon. With a time span of about 2-3 hours in between of "awake" time. Put him down to sleep when he is still awake, not when he is already asleep. Same time everyday. Same place everyday. This has worked with both my children, even though my eldest child was harder. He needs to learn to self soothe. I know it's not easy... my eldest child did not sleep through the night until she was about 4 years old. LOL. Yah, not easy. I was breastfeeding too, both of my children.
Maybe, he has problems with gas? My girl was like that and it really made her fussy and hard to sleep as well. Or, perhaps he has "reflux?" You might want to consider this as well.
Sorry I don't have a silver-bullet cure-all answer for you... but just wanted to share some thoughts and personal experiences. Hope it helps...
Take care and good luck,
~Susan
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