I don't think you're helping yourself get advice the way you have written your OP. You're ranting which is all well and good but your baby sleeps through the majority of the time it seems?
Your complaint seems to be that your baby doesn't fit it with your current routine?
To be fair WHOSE DOES?
I have 2 children, both amazing sleepers by any standards really but I know when their patterns change it knocks me for six because I JUST got used to it.
Even though I get a fair amount of sleep for someone with 2u2 I'm still tired and sometimes resentful that my life has changed so much so fast in ways I couldn't have planned for.
HOWEVER I'm not angry or cross at my children and my husband, although concerned about my hormones sometimes, does what he can to help practically and emotionally.
If you think your feelings are irrational perhaps you need to speak to your health visitor because your baby does not sound like a problem sleeper.
Maybe stop expecting your 7 month old to do what you want and go with his flow for a few days to see if you feel better?
Oh, and ignore smug unhelpful friends talking about how their children sleep. It's all bollox- you only ever get the show reel of someone else's life, the real stuff is on the cutting room floor.