Hi, I see your post is from a couple months back, so hopefully you have found some relief by now. I'm not breastfeeding yet, but have struggled a lot with anxiety and done just about everything under the moon (pharmaceutical and ''alternative'') to try to find some relief. I thought I'd give you some recommendations based on what has worked for me.
Bach flower remedies have been very helpful for me and are safe during pregnancy and breastfeeding. norskelove mentioned Rescue Remedy, which is the combo of Bach flower remedies that is supposed to provide relief to anyone, so if that is all you have access to it is a great option. But if there is somewhere that Bach flower remedies are available near you, it is even better to make a personalized blend. You can read about the different flowers here (http://www.bachflower.com/original-bach-flower-remedies/) and figure out which ones sound best for you and self prescribe.
Also, if you drink coffee, you should quit as soon as possible. Naturopaths were always telling me to quit drinking coffee - if your nervous system is already agitated and giving you anxiety, why agitate it more with caffeine. I never heeded their advice. But upon getting pregnant I quit drinking coffee, and the few times I have had a cup of coffee since then, I am amazed at how much it increases my anxiety.
Self-care makes a huge difference, too. You seem to have already figured this out by noting you need a break every day and a partner that validates your feelings. It is not selfish to take care of yourself and call on others to help you do that. Make sure you are doing the things that make you feel good, healthy, and happy to be alive. That means the basics like eating nourishing foods, getting a break and rest when you need it, getting exercise, etc. But it also means finding time to do things that bring you joy, having a partner who makes you feel loved and cared for, finding ways to express yourself creatively, etc.
This last recomendation is not an easy one and some may think it is controversial, but I truly believe it so will put it out there. Anxiety is always a manifestation of some deeper rooted fear you have. It isn't biological in the sense that you are born with some gene that dooms you to deal with anxiety. Years of suffering from anxiety can alter your biology (change your breathing patterns, affect your body and posture from constantly holding certain muscles tight, cause headaches, etc.). But to get at the root of it, you have to do a lot of self-reflection and deep digging to figure out what the deeply rooted fear is. For example, I have fears of growing and advancing and also of letting go to the uncertainty that is life. When I work on confronting those fears, I find relief from my anxiety. When I just try to figure out why I'm anxious about waiting in line at the bank, I think myself into circles and generate more anxiety.