Here's what happened:
1. SIL sent out an invitation to her main wedding event on FB. What this invitation included: a lot of misspellings, weird jokes about marriage, and 300 people, which is not the number we agreed to. What it did not include: the groom's name, my ILs' names, or any kind of hospitable greeting.
2. SIL followed this up with a rude email addressed to her FI, FIL, MIL, DH, myself, and someone I've never heard of ordering us to be in various parts of India on certain dates. She also said she would resent it if we got sick or tired during this poorly- planned trip. She also seems to expect DH and I to fly into Mumbai rather than Delhi, which isn't convenient for us.
3. MIL is very upset and she and FIL said they don't want to go to Mumbai at all to attend the reception there (hosted by the groom's family). SIL called DH (who is OOT at a conference) to have a tantrum over this.
*sigh* do people like this ever settle down? This is so exhausting!