I'm not against abortion, but I don't believe it's the best option in this case. If you feel that you can carry out the pregnancy without any significant harm to yourself, please do so.
Now, as for whether you keep the baby once it's born, it sounds like it would not be best for you or the baby to keep it. Adoption is not the only option for you though. It sounds like you and your boyfriend's parents are not capable of supporting your child, but perhaps you could pass care onto another close family member. That way you would still be close to the child, and could perhaps even take care back when you are older and more financially stable.
If you do decide to pursue an adoption, you may want to ask for an open adoption. That way, you can still pursue a relationship with your child if you wish. I think it is best to always leave that option open.
Lastly, if you do decide to keep the baby, this is a very personal opinion of mine but please consider marrying your boyfriend. It is so important to a child to have stability as he or she grows older. Also, like
>>7 said, you can look into support programs. Even the Dollars may be able to help.
Best of luck to you and your family, Juliette. I hope that this turns out to be a blessing in disguise for you, or at least not a cause of pain. Please tell us what you decide :) but also don't rush your decision too much (besides the concept of abortion); you have eight months to figure out the rest.
tl;dr Do what you can to keep the child as close as possible, as long as it is good for you and him or her. We're here for you :)