In any business, there is a continual barrage of people trying to take advantage. So taking a calmer stance is good-- not letting the opposition bowl you over. There is an emotional win that some people enjoy, stabbing and pinching.
As for legalities, you have every right and need to pursue your property. If she takes advantage of you, she will teach that to others, and they will assume it's okay.
Small things you can do:
1. Send her a certified letter with return receipt. That provides dated evidence that you tried to contact her concerning the terms of the agreement.
2. Let her know that you plan to file copyright for each authored/created item.
3. Let her know that you may take legal action, and give her the name of an attorney. (One you know is helpful, so she doesn't call them first.)
4. Put metadata tags on any files you have. If there are a lot, get them into something like Bridge, and gang-edit them. The files will already have a date stamp on them, so make sure those aren't removed.
5. If it seems appropriate, let her know that so far you have not defamed her publicly, and would like to keep it that way. She will know there's a lot of damage that can be done, and hopefully will not play ridiculous games.
6. Let her know that you recognize it takes time to remove files, and you will give her [one month] to remove all files. If she makes any profits from the files that have not be removed, you will need the full amount of the profit within 30 days of the sale/income.
If within 30 days she has not removed the files, you will send her a bill for hourly compensation for work you have completed. (Be careful how you word this or she might just say fine, and ignore it.)
(If she plays dirty, then contact her site host and let them know she has illegal content on her site.)
I fully understand the need to forgive, but there is no company that would want their employees to bow down to a thief and give away intellectual property. It is a given that you have rights to it, and not a matter of generosity or kindness to give that up. What you worked hard for is yours. Forgive, and expect ethical behavior of others.
Some people just don't know, so educate her while you communicate your intent.