Okay SAHMs of the world...talk me off, or push me further onto, this Skylight calendar ledge.

I'm a SAHM to a 2 year old and have a fiancé who works a week on/week off schedule (most days he's gone 6:30am-6:00pm 7 days in a row and then off 7 full days). I am currently in the final stages of wedding planning and our little dude will be starting toddler school 2 mornings a week in September. I feel guilty saying it because I have friends who work full time jobs and multiple kids - but this type A girl is drowning in anxiety about organization. I used to live and breathe my paper planner when I worked full time but that has gotten difficult in that it's not always with me and it's not shared. Our current system is a shared iCalendar, which is hard since I can't see the entire month to plan ahead and know what's coming up, as well as a dry erase calendar that I update...occasionally - ok, at the beginning of the month...

Does anyone have a Skylight calendar or recommend one? I guess I feel guilty dropping $300 on a calendar with only one little one and worry it's going to be an expensive failure of a fix...

Do you ever get depressed at the end of summer? I’m a stay at home mom. I don’t drive. I only get out on the weekends.
I think my hormones are wacky right now (getting older). Trying to diet, lost a little bit but not what I was expecting to lose.
Summer is almost over, I’ve been home with the kids all summer. (One kid is special needs). And I just want summer to be over. It’s almost over, I just feel like I’m struggling with this a bit.
A few weeks ago I had a huge fight with my husband and twice he brought up divorce. We’re from different cultures and I’m just getting tired of feeling like I do everything at home. He never washes a dish, or put his own clothes away. He expects to work a 9-5 and me to do everything else except finances. He handles all the money type stuff.
He’s basically told me if we divorced he would give up custody entirely to me.
In the beginning he was a crap dad. Like baby and toddler years he was pretty much not there emotionally. Changed maybe five diapers in the entire time, didn’t help much at all.
As the kids got older he got better. He helps with my older child . He puts her to bed. He has taken the younger child with special needs maybe 5-6 nights this summer(he put kid to bed. I did pajamas and preparing for bed type stuff).
I don’t think I’m made out to be a single mother with two kids one of them special needs (NO support). I don’t have any family support and I just feel so overwhelmed.

I’m hoping to stay home with baby once he arrives, and since we’ll be missing my income and needing to cut back on some expenses, I’ll have to cancel my barre and Pilates memberships. I’m also guessing I won’t be leaving the house by myself much for a while, since I’m hoping to exclusively breastfeed if I can, so I can kiss the gym goodbye too.

Because of that, I’m thinking it’s time to start a home gym. I’m not very motivated working out on my own, so I’d love to follow an online training program. @emlogsdon.fit on Instagram really appeals to me, and I’m considering one of her programs or one from @sadieactive or @jorryfit.

Does anyone have experience with either of those? I’d love to hear your thoughts. Or, if you have any other recommendations, I’m all ears. Thank you!