back to back longer stays on Esta with only 100 days in between

I'm a german citizen with an Esta. I've been to the us for the first time from Febuary 24th until April 6th to visit my girlfriend/now fiancée.
I have another visit planned from July 15th until October 3rd, we're going to Disney World with her mum in August and are planning to get married in September. I plan to then return home and start consular processing for a CR1 Visa from there.
I'm a bit worried now that i might face scrutiny or get denied at the boarder cause i'm staying for so long.
I genuinely do plan to return back to Germany tho.
Is there anything i can do to help my case or should i shorten the trip by a couple of weeks?
We already have the flight booked so i would have to pay a fee for any schedule changes that i would make.
I'd appreciate any help