Feel like I'm beginning to spiral

I've struggled with anxiety/depression throughout most of my life and it always seems to come in waves. This wave however, has seemed especially large and feels like I'm getting to a tipping point like I have in the past. I'm not to the debilitating stage yet, but terrified of it eventually getting there again.

Most of my anxiety stems from an overwhelming fear that each new little thing I find wrong with my body is terminal. The most recent development has been an eye twitch (more than likely brought on by work stress and allergies) but my mind has convinced me it's a beginning sign of some terminal illness.

This all comes at a time when I've been struggling with almost daily existential crisis, so I go back and forth between those two ideations.

I feel awful for my wife having to constantly deal with my fears and feel like it affects her more than she is willing to admit. I just don't want to get to a point where I'm a useless anxious shell again, but I don't really know how to knock myself out of this without some new medical fear taking its place.

I don't really expect answers, but it's just nice to get my thoughts out to people who understand at times.