Taking care of an active 18 month old is often an exercise in stopping them from executing their latest plan for self harm. This means many things get started. A few things get finished in a hurry and almost nothing gets finished well. Don’t let that be your business.
Stop just thinking about the business you want, and take some action to get to the business you want. Way to many freelancers just stop dreaming about success and never execute then complain about not being successful.
Sure you could argue about being called names by your client, but is it actually going to change their mind? Are you ever going to see them again? Don’t waste your time fighting with them, just be polite and move on.
The only thing you can actually take care of is yourself. Give your manager weekly email updates on what you’re doing and expected deliverables. Build out a training manual and give it to your manager so they can have it for the next person joining the team.