Perhaps a male perspective would help.
I am sorry this has happened to you.
It is very obvious that you have very strong feelings for your boyfriend. You would not be going through all of this pain if you did not. There is nothing wrong with loving someone. However, he clearly has some serious problems with being faithful, and that lack of commitment has now resulted in him fathering a child. This is not the first time he has acted unfaithfully and you are deeply hurt and confused. That is certainly understandable. He is not acting responsibly, at all. Indeed, he is being abusive of you.
What should you do? There are several best practice steps.
First of all I would highly recommend that you get some face to face support. A counselor who can talk with you about these complex issues is needed. You are emotionally being abused and are hurting. In a relationship such as this your perspective and emotions can/will be confusing and uncertain. An unbiased professional, like a counselor, can help you work through the choices you will need to make. Your family doctor can give you a referral to a good local therapist.
In the meantime, you have been deeply hurt by your boyfriend's actions. No matter what he says about the reasons for his actions, his behavior speaks loudly that he is uncaring. I would also encourage you, that you set some contact boundaries with him.
You need some time to process all of this. That time ideally should be alone, without him present, so you can think things through. If he truly loves you he will certainly understand this and respect it. He will stay with you and be patient if he cares. If he refuses, his behavior will tell you more about how he is more about himself than you.
There is no doubt that this is a powerful and confusing situation. You need time and space to think this out and the guidance of someone who will help you see your self value and worth. You can feel better about yourself, but you need the distance and space and advice that all of us need when these types of things occur. Steven