You are getting a hard time here - try and remember that if you want to reach a particular objective, it sometimes is easier to get there by being sympathetic.
18 months isn't very long to get over a marriage break up - especially as you had a child so quickly.
I honestly dont think you should expect this woman to want you near her house - presumably she is genuinely distressed by the sight of you. You must take that into account - it's not games here, it's probably real pain.
And it's your comments criticising her involvement in the marriage breakdown that seem unkind - you have no idea what the reality of that was, you only heard his side. Remember relationships are complicated - he was the one who left, regardless of the problems.
There is nothing wrong in wanting to be recognised as a partner, but you do need to be more sympathetic.
I think you'll find that you actually back off and say 'ok, I understand this is hard, what can we do to make this work' it will actually help things.
Why not tell your partner to call her, apologise for being insensitive and ask if there is a way to make things work - ie. warn her that you will be in the car as there is no choice, but in future you will keep out of her way.
If she feels SHE is getting some respect (as a very hurt woman) then you might get some back in the end.