I’ve spoken to my DH countless times after during the 28 years he’s been step dad to my son. He says DS is wonderful, infuriating, funny, irritating, talented, idiotic, sparking just about every emotion there is!
The difference is my DH was a full time step dad I think. Son’s dad was briefly married, she was not an exemplary step mum (what kind of woman calls a 5 year old a mistake & evil? Luckily Dad binned her, one of the most vile people I’ve ever met, not a jealousy thing because if son’s dad & I were the last 2 people on Earth, the human race would die out).
Son’s had lots of other step Mums who have been pretty much as my DH has been as a step dad; taking time, being open, talking about any issues, just being a good support - parents with kids do come with baggage - and good communication is vital between everyone. And yes, it can take years, and there will be many bumps in the road.
My favourite photo is of my DH & son’s Dad straightening son’s tie, mortarboard and gown just before his graduation. Just to see how proud they both were of our son justified all the hard work we’d all put in to make the relationships between all of us, rather like a giant extended family, as positive & filled with love & support as we could. Even if at times I wouldn’t piss on my ex if he was on fire.
When my daughter had to be homeschooled, son’s Dad tutored her for GCSE English & English lit - hey, he trained as a secondary Eng & Drama teacher, why not? Lol!
Sometimes it’s good to take the emotions out of the equation, as hard as it is, and focus on keeping the waters as smooth & calm as you can. Lead by example (but then that’s a pretty good motto for life anyway)! If you need time, take it. It’s a long road but there’s always the ability, with hard work, it can be a positive thing.