Oh, dear. Your mom sounds like a terrible problem. She's obviously in a great deal of pain, but knowing that may not help you much right now. She's hurting you.

So, what you're really saying is when you see your bf and your relationship through your mom's eyes, you feel bad. Viewing yourself as you imagine a critical, judgmental person might view you is really, really painful. Especially if the criticial, judgmental person is someone as important as your mom. And since you were raised by this critical person, you've probably internalized it as part of your self-concept. It doesn't help if your self-esteem is low.

Your mom is unlikely to change, but you can work on yourself and how you react to her. You may find she changes when you do. That, however, is the work of a lifetime. It doesn't help with your immediate problem. You probably need to set boundaries with her and not continue to engage with her when she's abusing you. Just doing that will raise your self-confidence and possibly make her think a bit before she opens her mouth to dog on you. A therapist can help with setting boundaries. Or there are probably good self-help books.

Just as simple a thing as imagining the kinds of conversations you might get into and preparing a simple one or two sentence response that firmly expresses your desire not to discuss the topic and ends the conversation is great. You can memorize your line and practice it until you can deliver it calmly. Then use it when the topic comes up. It's perfect for phone conversations, because you can just hang up afterward.

Right after my son moved out of the house - when he was 18 or so - he would call me and have the most abusive conversations with me. I just felt mentally battered afterward. My therapist at the time kept urging me to cut the conversation off when it became abusive. She gave me a line to use - something about I'll talk to you when you're calmer. I couldn't do it, because I was afraid my son would never talk to me again. Which is silly in retrospect. Anyway one day he was harranging me on the phone and I used the line. Just as I was about to hang up he said, "No, wait! Don't hang up! I'll stop yelling at you." And we went on to have a nice polite conversation. Beautiful!

On another issue: I was thinking about your comment about not being able to find positive stories from women in relationships with men diagnosed with sz. I assume you're looking on forums like this one. Keep in mind that the people who come to forums like this tend to be in some kind of pain and are looking for support. It could be you're not finding those positive stories because those women aren't visiting forums like this one. Don't lose hope.