I had to laugh at your comment about "clean eating" Amanda! That is too true! I also hate that I have to clarify every time I talk to someone about eating a certain "diet"... because I am just explaining my way of eating, not actually being on a diet, but that stupid word "diet" has become synonymous with eating less to lose weight... ugh.
I'm curious what the women at the Girl Scout leader dinner thought that a week of crying would accomplish? How exactly does that make a baby eat less at night? Are they actually trying to tell you to ignore any and all cues he's giving you regardless of hunger or anything he needs overnight just to force him to stay down in his crib? I don't understand that logic. I wonder what their views are on changing a wet diaper in the middle of the night too... 
Do you have any sound machines or soothers near/in the crib that Jasper could begin associating with sleeping in there? I have some ideas of things that might help him, since I've tried a million things with Sora... but if he's as picky as she has been, you might just have to keep tweaking things to find something that works. I can totally relate to losing the ability to sleep while nursing. I can only nurse Sora in bed for an hour or two max in the early morning, but unfortunately I'd never sleep if she were in bed with me all night. I prefer her being in her crib or pack 'n play, and she sleeps better too.
I do think getting Jasper to sleep in his crib is probably the best first step towards getting him to sleep longer stretches through the night. I've noticed if Sora sleeps in bed with me, she smells me and senses my presence, and she'll just keep going for the boob every hour or two like crazy, even if I have no milk left and she's clearly not hungry. Even if she's in the same room with me in her pack 'n play, she still seems to wake up more frequently than if she's in her crib in her own separate bedroom... I know some people are hardcore into co-sleeping in the same room, so I'm not trying to say that all babies behave like this, but it has been mine and a friends' experience for sure that our babies wake more from that.
Sora has a ridiculously hard time going down for bedtime (as everyone is well aware of!) and I might've just found a soother to help her. My step-MIL gifted the baby one of those crib aquarium soothers that hangs on the side glowing and making gentle sounds for the baby to watch and then drift off to. I never thought I'd go for one of those, but it actually has been winding Sora down better than anything else we've tried! She fusses a little when she's about to fall asleep so I pick her up for just a minute or two, she falls asleep on my shoulder, then I place her back down and she's asleep for the night. Some people are against sleep "props" but I am SUCH a fan of sound machines and now this aquarium soother. I think we now have like 5 or 6 sound machines of different kinds for this baby... oy. lol
Months ago when Sora was at a peak of waking up every hour or two and she wasn't in a growth spurt (it was lasting weeks on end of this frequent waking...) I read something online that was a lifesaver for us. First it said that sometimes your baby just wakes up expecting to be in the same position doing the same thing they did as they fell asleep, so changing how they fall asleep can help those types of wakings (if you're having any of those). Sora seemed to startle awake less when I stopped nursing her to sleep and setting her in her crib that way, which just kind of happened on accident anyway since she stopped wanting to nurse to bed most nights and I had to find another solution. The second and most priceless thing I read is that sometimes mothers are too quick to offer the breast at every waking. I thought that Sora must've been hungry every time... I just hadn't even thought about her possibly NOT being hungry and just waking to be put back down. All I did when she woke up for most of the wakings was pick her up, rest her head on my shoulder, bounce/sway her back to sleep in a minute flat, and then set her back down. It took me just 2 or 3 days of it and she was sleeping longer and longer stretches till she only woke maybe once or twice to eat at the same times so I knew she was actually hungry those times. It didn't even require crying.
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