Some people just don't like confrontation & may have nothing to do with people pleasing. Sometimes they hope that the other person will be the one who gives up & fades away when they don't willingly do everything the other person wants them to do with them.
Fading away is fine actually it is just a non-confrontational way of saying "I'm just not that into being friends with you" & is a hint that most people would take instead of making an issue out of it.
If she says she has to think about it....go ahead & ask those other friends. "IF" she finally gets back to you & you have made other arrangements with someone else....just let her know....no big deal. Don't wait around for an answer when most times you don't get one.
If that is something that bothers her (which I doubt it is) then the next time she will get back with you sooner IF SHE IS REALLY INTERESTED.
Don't let other peoples indecision or lack of response control your life.