My ex and I had been together for 2 years.  It was rocky for the last couple months when she lost her job and just seemed to refuse to look for work just living for free in my house causing me to have to financially support us both.  I also suspected she was cheating on me, and eventually I broke up with her and she left to live with her parents.

A few weeks later she comes knocking on my door to let me know she's pregnant with my child.  She was practically beaming with glee.  I agreed to let her stay with me again as my home would be a healthier place to stay as her mom smokes like a chimney and refused to stop smoking inside when she found out her daughter was pregnant.  Didn't want my child subjected to that.

The one caveat to this arrangement being we would go in a couple weeks and get a paternity test done.  She very happily agreed.  Her reaction actually washed away some of the fears I had about her possibly cheating on me.  So she lives with me for a couple weeks and we go to get the test done.  We find out that the child isn't mine and like a switch is flipped I honestly no longer care about that kid anymore and tell her to pack up her shit and get out of my house.

This was a week ago.  She moved her stuff back to her parents house, but is staying with a friend to avoid the cigarette smoke and other problems there.  She, her friends, and even a few of our mutual friends are texting and messaging me about how I'm a terrible person for doing this to that innocent child.  That I have plenty of room in my home and I should just help her out.  I feel like I've been through the emotional ringer these past months and I've been though every emotion I am capable of feeling.  From realizing I was possibly a father to the betrayal when her cheating was confirmed...honestly I feel so emotionally raw and sometimes I agree with them.  That maybe I should take her back and just care for the kid.

Was I unfair to this unborn child?  Am I a total piece of shit for not wanting them in my home in this vulnerable time for them?  She cheated on me, but is this a situation that I should suck it up and take care of them anyway?