Well, your issue is clear to me and I can relate to it. I left my job a couple months ago and my hypochondria has turned into vicious worry cycles, sometimes I have as many as 5 different worries in a day. Since you haven't provided much information for me to work on in a response (I'm known by some on this forum for lengthy detailed responses), I'll just suggest a couple basic words of advice. Find a time occupier, exercise, meditate, sleep well, get a therapist, and possibly a psychiatrist if the therapist does not prove to be enough. Also, there are medical advice phone lines and online chat services you can utilize if a doctor is unavailable to give you an examination that can be of help if not abused (if you call constantly, you build a reputation on phone lines. Everybody in Poison Control knows me and many of them used to think I was funny, but now I annoy them with the absurdities of the worries). Anyway, as for your partner... well my advice is to have a serious talk with them about how you are aware of how serious your problem is and that you will be seeking treatment. Ask them to be patient, but do not apologize profusely. It's not like you are doing this on purpose. You can tell them you regret the frustration you cause them, but I don't think heavy apologies will mean much. Apologies work for a while, but if the problem is repeated then they lose their worth. If you have had a talk before, then I advise you to possibly get away for a while and find another source of emotional support. The point is that your partner is obviously tired. Make things as easy as possible for them.

On another note, everything I have mentioned is long term oriented. As for what to do when a new worry suddenly emerges and you feel like terror is seizing you... that's something I don't even know how to address yet. I used to be afraid of illnesses like kidney disease, so I assumed I didn't have much time to live. If you wave worries like that, then I advocate just going along with the worry. Fighting it likely isn't getting you anywhere. So just enjoy life as much as possible. Go on laughing binges with friends. Enjoy the time you believe you have left. I'd elaborate more, but I think I've been poisoned (as always) and am just coming out of a contorted terrified stupor that seems to be on the verge of worsening again.

I hope what I said has helped. If you give a little more details on your situation, perhaps others or myself on this forum can provide you with more useful advice.