Moving in with a boyfriend

I'm not even close to being ready for this step but I'm just curious. If you have a child and you move in with a guy that isn't the child's father, how did you make it work? Like what if you two are ready for living together but not marriage due to college/work training. What if the father of the child is still in the picture?

ETA: And the relationship is a very serious relationship that there is a strong possibly of marriage for.

We were together almost 18 months before we even approached the idea of moving in with one another.

As per our custody order, I told my ex I was moving. I gave him an extra 30 days notice because of moving in with someone else which gave him ample opportunity to bring it back to court if he had an issue.

Nothing changed with my ex and I.....nor should it.

We just moved in together. We were staying with one another pretty much every say so there was no point in paying separate bills.

My son's father was already living with his girlfriend so there wasn't any issue.

We just moved in together recently after living separate for 2 years. My son is adapting well to having him around, and my ex is just fine with it as he has been living with his girlfriend for over a year now. Moving in with a serious boyfriend should have no effects on your child's father... You both have to move on at some point.