Hi BBW and welcome;
There's nothing harsher than being dealt a raw deal by those we love and rely on for guidance and acceptance. You must be feeling very isolated and confused.
I'm sure you thought telling your mum was the honest thing to do hoping she'd understand. It backfired unfortunately and here you are. I feel incredibly sorry for you and apologise that your post wasn't replied to until now. (Thankyou so much Jacko!)
At 21 I was raped by the love of my life and my mother said to me; "So what did you do to make him do that to you?" 35 yrs later and the penny dropped! I'd lived my life feeling like the cause instead of a victim.
Please don't let this incident (spitting in your face) affect who you are or what you think of yourself ok; it's her cross to bare not yours. Attraction is the foundation for love, not humiliation. Allowing others into that private space, especially those who mean harm, can't be productive or useful. It's your heart and body.
What your mum did was violent, not motherly. Please take it for what it is; abuse. Most of all though, it's NO REFLECTION of who you are. It's an off the cuff response to her fear, and maybe a deep feeling of disappointment that can't be expressed at this time. That's still not your problem, it's up to her to express herself properly.
I'm not sure what your relationship's like with your mum, but if this is any indication, you might want to take a step back and spend some comforting time with your girlfriend. Look after yourself because your mum obviously doesn't have your best interest at heart.
When you see this vision in your mind, it's because you're confused and self blaming. Maybe you could try writing your feelings down and read over them. It's not the end of the world, but it's definitely a troubling situation. I really hope you see these posts hun. I'm sorry again for your post being lost.