Hi this is my first post here a strange first post but I'm desperate for some advice.
First of all I'm not sure if I've posted this in the right section so feel free to move it.
Second of all I guess there are some adult themes in this post (if you can even call it that) so maybe give this post a miss if you are young or triggered by this kind of subject.

I'm pretty sure that I'm making a big deal out of something small but I'm a big anxiety sufferer and I'm not sure how to deal with a situation like this.

Just a warning that I do tend to ramble so thanks to anyone who manages to read the whole thing :P

Basically an old coworker of mine who was transfered added me on facebook.
I was friends (not close friends though) with him when we worked together and he use to give me a lift home when I worked with him. He knew about my issues with depression and anxiety and at the time I thought he was being so nice because he felt sorry for me as I'm quiet and tend to keep to myself (which suits me fine lol). We'll he had a reputation for being 'creepy' I always use to defend him and ask people why they thought that and they would just say there's just something about him so I dismissed them. There was also a rumour that he and a young co-worker were sleeping together. His wife came in store one day and one of my coworkers said that they have an open relationship and that they both sleep with other people. I thought that was a bit strange but each to their own I suppose. They do have 5 kids (one being 2 years younger than me) so I felt quite sorry for them.

Anyways thats enought backstory. He adds me on facebook and starts asking me about pictures on my profile. I breed lizards and had photos on my facebook and he started asking about them saying they were cute. He said that he should come round sometime so he could see them and that he'd love to hold one as long as it's not vicious. I hate people coming to my house but didn't want to be rude so I just kind of ignored that bit and said a few are tame but not all to try and avoid that part of the convo.
So the next message he send is and I quote "How would you feel if I came round sometime this week when your mams not home?" and straight after he sends "When are you working this week?"
Well alarm bells started ringing so I messaged my sister who is in uni for advice. She said thats definetely not an innocent message since he specifies that my mum be at work. She said just to say that I'm busy this week and to not open any more of his messages, wich I did. He sent another message after wich I didn't open but I saw what it said it said "U r OK with me coming round when ure alone right?" I've not opened this so far and I'm ignoring it.

The problem with ignoring him is though that he quite frequently comes in to where I work I probably see him about once a week what am I suppose to say to him if he comes in I'm overcone with anxiety thinking about, I havn't slept all night.
An even bigger problem though and a totally irrational one I keep telling myself is that he knows were I live what if he comes round un invited. I know it's irrational but things have happened to me in the past and the thought terrifies me and I can't get it out of my head.

The other thing I'm thinking is what if what he is saying is completely innocent. It's just why would he specifically ask twice if he can come over when I'm alone.

So my question is what would you do?

Im thinking of either doing what my sister advised and just ignore him but that doesn't get rid of my anxiety over it.
Another option wich I think might be the right thing to do is just to outright ask what he is suggesting and when/if he clarifies just say that I'm not interested.
Option 3 wich really is a last resort is to tell my mother. I rely on her alot since she's always been there to help me but she is very protective and I know she'll go completely over the top if I tell her. A big part just wants to tell her though so she can protect me. I'm an adult though and I need to start dealing with things myself.

What are your guys suggestions/experiences?

Thanks for reading hope it makes sense and isn't just a load of incoherent rambling lol