Would it be horrible on my part to abort a baby I actually planned? (Consider the cirstances)?

I'm 39 years old and I'm pregnant with my fifth child. I can see that I'm in for a very stressful pregnancy, so I've been thinking of terminating it. My boyfriend and I have been together for 10 months. has cheating on me constantly and I'm sick of it. One of his little tramps even called my house and threatened me. He also used to hit me but he stopped once he found out I was pregnant. He wants this baby badly. I am trying to work with him because he really wants to change. He's 24( a lot younger than me). He has turned his life around in many aspects. He spent five years in jail, now he has a good job. He's very blessed. No more crime and I love him and respect him for that. We fell in love fast and we planned this baby. But I don't think he's ready even though he would be pissed if I abort it. This will be his very first child. I just can't be stressed because it may just end in miscarriage anyway. I lost my job last year and my boyfriend is a huge financial help. Not to mention, I love him so much, so I don't want to leave him. But I don't think now is the time for us to bring a child into this world. However, I'd feel horrible for aborting a baby that was planned? What should I do?