My dad started dating someone new two weeks after my mother died. The way he introduced the fact he had a new girlfriend was "I have a new girlfriend and if you can't be happy for me then you're going to lose your dad as well" (it honestly seems ridiculous to even type that but it is genuinely word for word what he said to me). I was 23 when my mother died and my brother was 19.
There was a bit of bad blood between us, namely because I for around 3 months almost refused to speak to my dad after the aforementioned comment. During this time she suggested to my dad that I had emailed her colleagues (which I had not done). She has plenty to say about my brother and I and I've overseen messaging in which she spoke about us as if she knew all our personality flaws.
He did not introduce this woman to us for 3 years until, after much pestering (as I felt it was extremely unusual that we hadn't met her) he finally introduced us over a brief lunch (brief being around 90 minutes) about a year ago. He has not made any suggestions about us meeting again.
This weekend my dad casually dropped into conversation that my brother and him had stayed at her house and she had cooked the both of them dinner. I am extremely hurt by this as, surely if you are going to properly introduce your long term girlfriend to your children, you'd do that with them together? After all he said to me and after all I've put up with after my mum died, how can he have been so heartless as to have done that?
Am I being unreasonable to be upset with the way he's dealt with this?