Hullo and welcome!
My mum has cancer too, and I have been involved with death care of two close family members. So I do feel for you.
Is it possible you are trying to create some sort of diversion from a difficult life situation with this man? Did you break up with your ex while your mum was dying? I truly get (I have been the live-in caretaker for both my mum and girlfriend these past few months) the need to take a break, go out and do something fun. You have to be strong for the sake of those you are supporting, so you really really need somebody to console and support you too. There is nothing selfish or evil in this.
However, there is a time for everything. A lot of your emotional energy is invested in this guy at the time when you need all the energy you can get.
I don't deal well with emotional unavailability. That is not something I want or need in my life. I think you need to ask yourself a) is this guy atm available to me in a way I would want and need? and b) is he ever likely to be?
Lots of love and power hugs! You are not alone.
Me: bi female in my twenties