Well, be sure you can communicate about important topics before you get married. But generally it's best to NOT jump in with "I don't want to have her living with/relying on us until she's 30". Ask him how he would react if SD said she wanted to move in after college and go from there. Also talk about money and how it will be spent. Does he plan to help her? In what ways? Maybe don't put your money together unless you feel OK about the money area.

These are important things to discuss - don't let fear of losing him stop you. You will regret it later.

I'd approach it by pointing it out in others and getting DH's opinion. "Oh look at mary, next door's son. 24 years old, doesn't work, doesn't even mow the lawn. I would never be able to tolerate that!"

"Bobby's daughter just graduated from high school, and does nothing but play on her phone all day. I couldn't live with that" 

People are much harsher on others kids. When he agrees with you...

"Oh honey, i'm so glad we are on the same page and you won't allow SD to live here without going toschool, a job, rent, helping out. (whatever your limits are)"

Hammer it home.

we have sd22 graduated from university with a bachelors degree in business and on advice of stepdad who contributed no money when she lived at home with bio mum, completely isolate her and younger daughter for mum to solely handle finances and cost of feeding them, stepdad told her to work at a friends petshop and buy into a franchise(with no money of her own) and sd22 has told her dad to not forget paying child support to her (this is 6 yrs after she cut off all contact) from bio mum creating the pas. 

She claimed she handled the expenses of sd13 along with bio mum, wrong bio mum barely uses any of the child support hubby pays her for her expenses (something hubby did not know because she ran off and kidnapped them)

so i asked hubby directly when is sd22 and Ss20 gonna keep getting $1000 per month from rich daddy because hubby no way will be giving the same handouts to our 2 toddlers which is hypocritical and there was no savings put aside for our kids and with the dysfunctional relationship, we cannot rely on sk to have our kids best interests and welfare to heart as they have never cared about it. The skids are so self centred and greedy and pampered by hubby, they see hubby as their bank and aren’t ashamed of it

i asked hubby how long he will continue to pay and he said when sd finishes uni and gets her graduate job maybe for 1 yr max so she can build savings. I said good luck because she has showed no motivation to be self sufficient and has made very poor choices, its like bio mum, step dad and skids themselves are trying to sabotage their future so rich daddy can give free money.

sd sat in silence at first job interview her dad pulled strings for her to get and laughed about it and then made no effort to get a job since or look for one. So if she is sabotaging her future and not making an active effort to get a job, why should me and our kids and hubby pick up her slack and give her money indefinitely that should be going towards kids who need the financial support??

hubby is also on 2 yrs contract so no guarantee contract is renewed at the end and he also said if he does not get contract renewed and retires early, tough he isn’t paying child support to sd22, ss20 she’d have to figure out her own finances and get a job

i asked hubby if he thinks she’d chuck a hissy fit and hubby isn’t sure but all her actions point to she will create drama

bio mum had an epiphany that my husband has 2 toddlers and her youngest child is 13, the only one who should mandatory receive child support which means in about 4.5 yrs she is no longer eligible and she is trying to get kids to do dirty work and guilt hubby because hubby has a higher financial responsibility to our kids who haven’t started school yet and exwife knows this but only cares about her kids like they are the centre of everyone and hubbys universe only