SIL help

My sister in law is so mad at me . She has been trying to have her first baby for over 2 years now and she's had a few miscarriages . My husband and I have been married for 4 months and im 8 weeks along . So far I'm having a healthy pregnancy so I decided to put it on Facebook . She then commented on my status and put "wow" then unfriended me. We never had problems in the past so I thought this was really strange .. so I messaged her . Asking her what was wrong yadda yadda . She pretty much said that I got pregnant on purpose to make her jealous bc I know she's been trying for so long ? I don't get it . How do you respond to that