Fatal Attraction or paranoid

While my husband and I were separated, he was dating a woman in another state. She did not ever meet our children nor did they know about her. She would give random, generous, gifts to them, and my husband would pretend that they were from him.

She started sending packages (cash, candy, several $50 to $100 gift cards, shirts, etc.) to the family home on holidays. Again, my husband would pretend that he bought the gifts. My husband would quickly retrieve the packages, and tear off the return address. I knew about the source of the gifts, did not like that they were sent to my home, but looked the other way.

Because I initiated the trial separation, my husband having a girlfriend was not an issue. I was also dating.

They stopped dating more than a year ago, have not physically seen each other but still text infrequently. My husband and I are trying to reconcile.

I just found out that she recently mailed, to my home, $500.00 to my adult daughter for her college graduation and a $500.00 watch for my son's high school graduation. I also discovered that she has been emailing my daughter. The gifts were given to the children without my knowledge. My husband states, "I never told them to keep it a secret." I am appalled that he even passed the gifts on to the children. My daughter knows who the money is from and my husband gave her the former girlfriend'a address so she could write a thank you note. My son thinks that his dad selected and bought him the watch.

I believe this was inappropriate, troubling, strange, and I question her mental health from this action. I told my husband to tell her that all contact to my children must stop. My husband tells me -- She thinks you are the nut. What sane person tells you to screw off for being nice. She gives milestone gifts to all her friends kids. She says she does not believe she ever crossed a line.

Am I unreasonable, from a safety standpoint, for being freaked out by this?

TL;DR Husband's former mistress sent my kids expensive gifts. They have been broken up for a year. She has never met the children. She lives several states away. Husband and I live in the same house and are trying to reconcile.