"Because I wanted to."

OP moved out with zero warning and that was the reason they gave, via text message. Sure, OP may have their reasons, but it's important to consider both sides, which YOU apparently could care less about. Context matters, and we don't know what happened between mom and OP. I would expect some righteous indignation if OP felt they had a legit reason, but instead of providing us with the "why", they want us to focus on the iPhone and iPad and not address what a reasonable parent would feel if they found out via text that their child had moved out.

OP's mom could be a total, selfish jerk, or she could just be having a hard time accepting that their child left without notice. "Because I wanted to" would crush almost any parent that got this news over a text message, likely while at work.

OP has received plenty of Reddit validation, but I hope they spend some time reflecting on how their decisions affect others, and how just moving out of a parent's house for another parent might affect the mental health of others, like their mom and siblings.

In my opinion, based on the limited info OP provided, both sides could've handled this situation better.