I had a similar situation once, many years ago now but it played out almost exactly like this.
I had been given all the promises of living together, marriage babies etc. We got engaged (sort of... he bought me a ring but refused to discuss weddings because, and I quote, "Why do we need to get married if we are engaged".....err.... should have seen that red flag for what it was but I was very young) and I found out I was pg. Then suddenly we had no future if this baby was born, I NEEDED to get an abortion, it would be totally selfish of me not to, and then the big guns.....his parents were very rich and he said that they would fund him to make sure he never had to pay a penny for said child. Looking back now I can see that he completely future faked me to keep me in his life. He knew I wanted the settled life, he didnt but didnt want me to dump him. I think he also knew what I can now see, that I was completely out of his league and he would never get someone else like me in a million years. Thats not me being arrogant, I was (note the past tense!) pretty, slim, dressed well, intelligent, popular....crashingly low self esteem though so I was grateful that he, anyone, wanted to be with me. :(
I had the abortion, dumped him and moved on. I am very glad I did. I look back and I would have had 28 years (so far) of that shit head in the back ground even if he hadnt seen the child. I would have had him hanging over me as I know his family would have loved the child and wanted to see it.
Sometimes there isnt just a wrong time to have a baby but a wrong person to have it with. Sadly we dont always find that out until after the deed is done, then its down to damage limitation.
Right now you need to limit the damage to YOU. And I will be honest and say that you sound quite fragile and maybe not in a place to stand up to him with a big fat fuck off. There is no "best" way in a situation like this, but there is always a "least worst" way. So if a termination would be the least worst way for you to get through this, then so be it, but please please do ask for counselling from the service you have booked it through. They have to offer it and can signpost you for further help if you feel you need it.
Take care of yourself sweetheart, take each day as it comes and try not to pressure yourself xx