I am really taken aback that you join him and his ex wife on vacations. So he and his ex wife vacation together? I’d certainly stayed home if my husband took his ex to join us on vacations.

Now i don’t think it’s your place to advice re diet or mentor his children. I can’t imagine dating someone and boyfriend criticize what my kid eats. Yes it sounds like they eat unhealthy but this is recent relationship for you and kids have parents. I am also confused on a concept of being their “mentor”. Why?

So the goal is NOT for you to be ever a stepmom? So you two never plan on commiting and you always plan to join him and his ex wife when they do things?

Both my husband and I have kids from first marriages and I know many others who have kids from previous marriages but I have never heard of someone assuming a role of a “mentor” to kids of a significant other. I’d not plan to mentor them if I was you.

Yes your place in this picture is confusing. Nothing wrong with being amicable with exes. I and my ex are friendly but your boyfriend and his ex might not be over each other. I don’t know any divorced people who are vacationing together. Why? If I still wanted to vacation with my ex, I’d stay married to him. And it confuses kids. They might think mom and dad are in open marriage as dad brings his girlfriend along to family events.

As about drinking. I don’t drink and neither does my husband. I had drinking partner before and drinking or drugs are total deal breakers for me. It depends what you think and feel about it. We can’t tell you if it’s bad.