I've been burned pretty hard by getting very emotionally involved in a SD?SB relationship. And she was far older than the average SB. However, there were some clear flags that I overlooked. I would take it one step at a time. If you really start to fall for her you need to really see who she is.
Why is she still a SB at her age? If all she knows is how to look hot for you, then get your kicks out of it and run. She has decades of experience of being paid to look hot and that's all she has.
Would she want a real relationship or be completely exclusive to you? If she's not willing to only see you, that's a clear sign.
Is she only looking for FWB? If that's in her profile..... At her age? WTF?
What's her family, kids, marriage/divorce situation? And really find out, not just what she says it is. There's always something fishy going on with much older SBs. Multiple divorces, kids, meaning very unstable.
In my case, she swore we were exclusive. She had a job that included 'travel'. It turned out her 'friend' was her real boyfriend. Her travel for work was her seeing SDs in other states. My advise, be very careful.