How can I get rid of this feeling?

I'm 4 months pp and recently returned to work. I am working from home two days a week and three days at the office until January. I was supposed to be able to keep working from home one day a week as of January but my boss has recently informed me that come January there will be no more working from home. This is because others started asking to work from home and she does not want to allow that so I lose the benefit. I understand her point but I'm also upset because this was something that was offered during my interview two years ago and one of the main reasons I took the job. I am thankful to get the two days until January but I am starting to resent my job and I haven't even started being in the office 5 days a week yet... I dont want to feel this way.