absolutely gutted

Just after Christmas I found out I was pregnant both my husband and I were so excited we couldn't of been happier then at nearly ten weeks I miscarried I think we're dealing with it ok but I can't help this massive feeling of guilt and  it's killing me to feel like I have to go through it all again and it seems to feel like it's being forced on me to be happy for others as my younger sister is pregnant she's about 13wks along now and I know deep down I am happy for her but finding it so hard to show it ( she's been through it 4 times herself) does anyone have any words of wisdom as I don't / can't talk to her about it as I don't want to drag her down now she's finally happy