I have been with my boyfriend for about a year now. I have known him for almost 5 years. He was an amzing single dad and has done great taking care of his two girls on his own. We have hung out with the kids a few times when we first got together and I knew right away the youngest was going to be the issue. 

Backstory:

My fiancée and I have been together for 4 years, both bringing in a daughter from previous marriages. My SD's bio mom is a meth addict and got all three of her kids taken away and so we decided to move 2,000 miles away to start fresh. 
Bio mom sold my SD for $200 at one point, let's her down on a regular basis and drops off the face of the earth for sometimes 8-9 months at a time...