Should I be mad/upset?

Kati
Ok this is kind of a rant but I'm so pissed! I booked my baby shower months ago and let my sister in law know because she is always busy. Well she just texted me and asked if I've already paid for the venue because her husband is in a wedding out of town that weekend. Meaning can we change the date.. Um yes it's booked and no I'm not changing it. I probably couldn't even if I wanted to because this venue is very popular and books up early. Well I lost twin girls last October at 19 weeks and had already planned a shower for that November and she had asked me then if I could change the date also. I said no then too. But I think it's so rude that she has asked me to change 2 different baby showers now! Plus her husband has been in literally 10 weddings the past year, I think it would be ok if she had to miss it or meet him later that evening. My husband and I have been through a really rough year losing our twins and I'm high risk this pregnancy as well. All I'm asking is for her to show up one day is that too much to ask?! Ugh!!