OP, your step daughter has only known about your pregnancy for a week. She probably does not hate your pregnancy. If you have been crying throughout your pregnancy , if can't have been because your SD hates your pregnancy given that she knew nothing about the pregnancy.
A 13_year old can be pretty self absorbed and is probably unsure how this change will effect her life. You probably have given considerable thought as to how this pregnancy is going to change your life. The 13 year old has only had 7 days to begin to think about the potential impact on her life.
You can have a perfectly normal pregnancy even if the 13 year old is less than excited about the pregnancy; many teens don't get terribly excited about the pregnancy process.
Her feelings may be very different when their is an actual baby. There is nothing that you can do to impact any feelings of insecurity that she may be experiencing, that reassurance if needed will need to come from her father
You should focus on having a normal pregnancy , and that can and does happen in many households even when older siblings are not terribly interested or excited about the pregnancy process.
Her father should continue to have as normal a relationship as possible with his daughter. If you make his daughter's reaction pivotal to enjoying your pregnancy, you the only thing that you will accomplish is making yourself miserable.
Leave her alone as she works through her feelings with her father.
The most helpful thing that you can do for both you and the daughter is to recognize that you are 2 females going through processes that are new to the both of you , and each of you will be adjusting to your new reality.
There are no quick fixes, and you each have months ahead of you to navigate the process.
Better you have no fantasized expectations about her reactions , and recognize that at the moment you will be focusing on gaining a baby while she may be focused on the prospect of losing the relationship that she currently has with her dad.
Time and respectful distance can be an ally for both of you.