Do you not have a green card yet? You need to cool down, consider your options, and possibly contact an attorney. He is your husband, so you have legal rights and he would have to pay support. You wrote that he is having an affair with his secretary. Nowadays, it is rare for a person to have a secretary because everything is electronic, so he must be in a pretty high paying position to have a secretary - right? You also wrote that you have been married for two years, so you probably have a green card application in the works. That means that you can have an employment authorization - not that you'd want to work with a newborn at home, but at least you have a legal right to work, which many people simply do not have. If you go back to your country - which, based on your geographic username, is having more than its fair share of problems now - it would be much harder to collect support. Your best bet is probably to separate from him but not divorce him, get support, and eventually find a job. You need to talk to two lawyers - an immigration attorney and a family law attorney. You are in Boston - not in the middle of nowhere - so there must be plenty of free and sliding scale resources for you. Go to a Legal Aid clinic, present the situation, and ask for advice and help. You are not helpless - since you are married to the guy, he has legal responsibilities with respect to you and your baby, so you just have to ensure that you enforce those responsibilities against him. What you are doing now - being shocked and figuring out his frame of mind - is useless. Call the Legal Aid instead. Once you have a baby, every logistical step, such as sitting in a legal aid office and waiting in line, would be harder, so you need to act now and act quickly.

Good luck.