Where do I begin without writing a novel?

A little history:
BM literally abandoned SS and DH to move to another state. I met DH AFTER she had been out of their lives for quite some time. She has always blamed me for their divorce. When DH, SS and I began living together (DH has primary custody) I invited her over to see our apartment at that time. I assumed that a 'mother' would want to know where her child is living. I assumed wrong. She declined my invitation, called me every bad word possible and accused me of trying to take her place as SS mom. I even helped SS pick out flowers for her for Mother's Day, against my DH's wishes, and that was ill received as well. For 3 years after I met DH she tried to get DH back. It finally stopped when she remarried. I have long since ceased to go out of my way to be kind to her.

Birthdays:
The first time she was invited to SS b-day party, she declined the invitation b/c I was going to be there. After she remarried, she requested to be invited. We invited her. She did not show up. She did not call us. When DH called her after the party, she said that she was hungry and stopped to get fast food instead of coming. We had plenty of food at the party. This past year, she insisted on being invited. We left it up to SS13 to decide whether or not to invite her. She was invited. Once again, she failed to show up. Just several months prior to this she had started to pretend that she wanted to be involved in SS13's life, which is a rarity for her.

Fast forward to now, which is 8 yrs later, BM decided to get weight loss surgery. Over the past few months she has made it a point to send text messages to my DH on a regular basis telling him how she's going to 'get back into modeling' once she has the surgery. I realize that ugly people can be fashion models, but they still have to meet measurement requirements. If you're 5'4" you will never be a fashion model. At the very most you MIGHT be able to do auto modeling or promo modeling, but you actually do have to be attractive for that. DH & I think her delusion of modeling is humorous, but it's really irritating that she is once again trying to impress my DH. I thought we were past that. I wonder if her husband has noticed how many texts she's been sending to my DH. BM did not take SS13 for 1 of 2 wks that she was supposed to have him over the summer. She did not see him b/c she scheduled her surgery at that same time. It was questionable whether or not she would take him at all this summer, but she did decide to take him for 1 wk. In the past 2 weekend visits that she had prior to this, she did not feed SS13 dinner, yet she insisted that he stay at her house later until 9 PM. She also did not feed him breakfast on some days and did not have food for him to fix for himself in the house. DH confronted her about it. The 1st time she literally told DH that SS13 never told her he was hungry. Really!?! She didn't feed him b/c he didn't tell her to!?! The 2nd time it happened recently, she just got defensive and told DH that he could talk to her husband if he wanted to discuss it. Instead of taking responsibility, she was going to hide behind her husband. I told SS13 to make sure he reminds them to feed him and to call us if they don't.

DH picked SS13 up today. SS13 often rambles on talking to me about everything. He trusts me and sometimes likes to talk non-stop. Today he told me that BM does not approve of him being assigned to do household chores by me. I've raised SS13 for longer than she ever did at this point. I don't care if she approves or not. I may not have given birth to him, but he is my kid and I will not be told what to do in my household. His summer chores are things such as reading, French lessons, light dusting and pulling weeds. His combined daily chores should not take any longer than 2 hrs max per day if he focuses on them. It's not extreme in the least bit. SS13 also told me that BM's husband put a list of phone numbers in his shoe and told him to call one of the listed numbers 'if anything ever happens'. SS13 said that there was no prior discussion and that BM's husband did not explain further. The numbers were given to him on Monday. He came home today on the following Sunday. I asked if he had been left alone at their house where he might need the numbers (although it would be weird to put them in the shoe in that case) and he said that he was never left alone. That leads me to assume that BM and her husband are implying that 'something' may happen at our house. The phone numbers even included BM's husband's parent’s phone numbers and BM's sister's boyfriend. I asked SS13 if his dad knew about the numbers. His response was 'no, should he?'. I told DH about it. DH & I instructed SS13 to write the numbers on a notecard and to keep it in his wallet. We told him to tell BM & her husband that we had instructed him to write the numbers on a notecard instead because it's gross that it's been in his shoe all week. We want it to be clear that we know about it, but also want to be clear that we have nothing to hide and that SS13 is welcome to have their phone numbers. I did, however, inform SS13 that if someone who is not authorized to pick him up from school tries to do so, he is not to go home with them. I did inform him that kidnapping charges would be filed if BM's husbands parents or BM's sister's boyfriend ever do so. SS13 also previously told me that BM's sister wanted to come to our house and visit. BM told her that our house is in a bad neighborhood and that she shouldn't visit. BM lives near streets known for prostitution (Harry Hines, Dallas) and has bars on her windows for safety. We live in a city that was rated one of safest places to live in our state. DH contacted BM's sis and let her know that she is welcome to our home at any time.

Ugh....I thought the lack of proper care in her home ended years ago (there's a long past). I thought her trying to pursue my DH ended when she remarried. Evidently, I was wrong.