Started my first office job. Everyone assuming I can afford to chip in money.

I hope this is the right place to post this.

I started my first office job last month, and I’m not sure how to navigate the office politics, so to speak. I am in a very tight place money wise, barely affording food at times. My boss has been passing envelopes around lately for so and so’s baby shower that is taking place in our office. I have another co-worker we are apparently throwing a wedding shower for, and everyone is expected to chip in for gifts for that, as well. And even with birthdays.

I have social anxiety and am not sure what an appropriate response is—not only can I not afford to chip in, but these co-workers are not very friendly nor welcoming to me and I barely know them. My boss has asked me when I’m going to add to the envelopes and I said I’m not sure I will. She looked aghast. I just feel awkward because everyone else is chipping in for gifts and I’ll be the only one who is not. Has anyone else been through this? Any advice is appreciated. Thank you!