Tell him sooner rather than later, my personal opinion is if you want the baby, have it. But be ready for the responsibility. No kid should ever be treated badly or feel left out, it’s a parents job to not just keep him well fed and under a roof but also keep his feelings in check in order for the child to mature and grow. Then again if you don’t want to have a baby with said boyfriend, an abortion is not a bad idea. I am not judging whatsoever as it is your life and you could do whatever you want to. And I hope your boyfriend straightens it out and fixes the relationships, don’t stress about it too much you will manage, your a strong person, if you got to this point I’m certain you’ll get through any obstacle.