I need advice, how do you explain anxiety to someone who just doesn't understand?

I'll just tell my anxiety history first, for a little background. I had my first anxiety/panic attack when I was 9 years old and I am now 22. I couldn't tell you what kind of anxiety I have (panic disorder, generalized, etc.), because when you're that small doctors shy away from labeling it and any doctor I have been to as an older patient has only told me that my case is "severe." I'm anxious daily and have been for as long as I can remember, and it has impeded on some aspects of my life but the intensity and situation varies. When I become overwhelmed with anxiety, I have attacks with hyperventilation, racing heart, and irrational thoughts about the intensity of the situation (a feeling of impending doom). I am not medicated as the actual attacks (with hyperventilation,etc) are not frequent enough to warrant a prescription, and I honestly just don't want to be. I've tried counseling and coping exercises before, once when I was little and another time last year but I don't feel that it improved anything. I honestly just don't know what it would be like to not have an anxiety disorder-I've never had a lifestyle without one. However, after living with anxiety daily for so long, I can function with it pretty well.

Here's my current situation: I have been dating my boyfriend for a year and a couple months. He just does not understand my anxiety issues at all, and is not alway sensitive to them either. We've had countless fights over the issue, and I've tried to explain where it comes from and what I experience but he just does not understand. To him, it's something that I don't try hard enough to control. In November I had one of the worst attacks I have probably ever had, and he broke up with me because he said he couldn't handle my anxiety anymore. We got back together, but I honestly have never felt like such a freak before. I went to a counselor and realized how much of my anxiety came from perfectionism (nothing's ever perfect so I spend a lot of time worrying over how I can make everything better), and tonight he told me "Don't you think you're giving yourself too much credit by saying you're a perfectionist?" That stung a little. He always points out how he feels it is "impeding on my life" and how trivial and stupid the situation is. He equates it to a normal persons anxiety and doesn't understand why I handle it so much worst. For example, I hydroplaned last year and now I freak out when driving in the rain, I call him that last time I had to go somewhere in the rain and he said, "Oh god, I thought we were through this." Whenever he talks about it with me, I end up feeling very belittled, disconfirmed, and flawed. How do I explain/show to him that an anxiety disorder is not something that is ever fully going to go away, and just get him to show some support towards my disorder? Has anyone else had to deal with something like this and if so, what did you do?

tldr: My boyfriend doesn't understand my anxiety issues, how can I help him understand?

Edit: Thanks everyone, I'm pretty sure we're going to have a talk tonight. I'm going to try to equate it to how he feels when anxious, as many have suggested (though I don't think I can force feed him coffee or drugs). And possibly show him this thread if need be; maybe it will make more sense to him if it's not coming from me. THANK YOU for responding though, everyone has been so encouraging!