You are blessed. You are very lucky. I just had my 2nd miscarriage. I miscarried twins in April and 2 days ago my singleton. I have a 4 year old daughter I'd love to give a sibling to. So just know that God only gives you what you can handle and everything will work itself out.
Sorry for your losses, but I disagree with your viewpoint. I've also experienced losses, but that doesn't mean that an unplanned pregnancy that the OP may or may not be prepared for (physically, emotionally/financially) is a blessing. An unplanned pregnancy comes with it's own challenges and struggles, that are not for anyone to judge. Just because we've had losses doesn't mean the OP is "very blessed and lucky" to be pregnant mere months after delivering twins.
Very much agree. OP, I think it's completely worth it to talk to your husband and your doctor about you own health, and also talk about the financial and mental health of the rest of your family, including the two LOs that you already have! It might be that this is "do-able," but if it's not the best thing for your family, it's OK to choose an abortion.
Also, I realize that you fear judgment, but I think that you're not at a point where anyone else needs to know that you're pregnant, and you can keep this decision between you, your husband, and your doctor (though I don't know which state you live in, and I realize this is harder in some places than others?). I think it's OK if this decision comes down to what's right for you, and for the family you have now - if that's another baby, then great; if it's not, that's also a completely valid choice.
Another thought - if you're not comfortable discussing this with your regular OB, is there a Planned Parenthood near you? They will be able to confirm the pregnancy, and also listen to your concerns without judging, and let you know what your options are.