First of all, you are AMAZING!
Every time, you lost the weight - and every time, as I see from your ticker, your starting post-pregnancy weight is lower! Also, given your history of ED, anxiety etc., it's pretty impressive you decided to breastfeed, because, as you say, bf makes losing weight a lot more complicated for many of us.
I know something about that. Currently breastfeeding my second lot of twins.
I wake up hungry and I go to bed hungry and if I'm not hungry, I still eat, because I'm exhausted. Sooo much fun, isn't it? BUT! It's totally worth it. For you, and for the baby. Actually I work as a medical translator and I just happened to finish a major project, translating dozens of scientific articles about breastfeeding and its positive impact on both the baby's development and mother's health. I felt quite encouraged to carry on breastfeeding, even though my younger twin girls are approaching their first birthday.
You are a mother of four so you know it all. About losing weight while bf, I would just point out that it's the first weeks that are impossible, because you need to establish your milk supply. Around month 3 I found out I could pretty much eat anything (or nothing at all) and my milk would still be there. Maybe I'm lucky that my milk doesn't go away, but I'm thinkjng - there are women in Africa who BF for years and years! So once the supply is established, I don't think going down on calories (within reason) can endanger your bf effort.
Plus, bf makes me so hungry I'm really not at riskt of restricting my calories TOO much if you know what I mean!
Anyhow, I wouldn't be hard on myself during first 6-8 weeks, your body needs time to adjust, your hormons need to find a balance. Just don't overeat on chocolate and junk, it's not good for your or the baby anyway. And once you're back to some sort of normality, you can start experiemnting with calories intake. I'm pretty confident you will find your way around, you've already done it three times, and the fourth time will be the charm
BTW, don't beat yourself up about pregnancy weight. I've went through two twin pregnancies, I watched my sister go through four prgnancies, and many of my friends, and it occurs to me that for many women there's actually very little they can do about gaining weight when pregnant. Some bodies are just like that (my sister's, for example): they REQUIRE the extra calories. I wouldn't need my sister to even tell me she's pregnant: the second I see her really stuffing her face, I just know I'm in for another niece or nephew
And if you are like that. it's because your body knows what it's doing.
And anyhow, you will lose it again. Good luck on your last journey!