I (25F) don't know how to support my husband (25M) with his career crisis

My husband (25M) and I (25F) have been together for six years and married for three. Financially, we’re stable. We both have steady jobs, can comfortably pay our bills, afford vacations, care for our two cats, and have savings for emergencies. We rent a home from family and, objectively, we’re not in immediate financial trouble.
Over the last several months, though, my husband has become consumed by fear about the future. He works in tech and has grown increasingly unhappy because of layoffs and AI. Since then, he has bounced between countless career plans. He applied to colleges, then decided against school. He studied for new tech roles, then decided to stay where he was. He applied for trade jobs, then wanted trade school. After getting rejected from several positions, he decided on getting his CDL, bought books, researched schools, and planned to quit his job for training. Then he changed his mind, accepted that tech might be better, interviewed for another position, declined the offer, returned to the CDL plan, decided he couldn’t do it, wanted trade school again, regretted declining the tech job, and now wants to pursue the CDL again.
Throughout all of this, he has become obsessed with the possibility that we’ll lose everything. He constantly talks about becoming homeless, losing our jobs, needing roommates, family members dying, and asks if I’m going to leave him. He’s even suggested getting rid of our two cats and selling our belongings to prepare for a future that hasn’t happened.
He’s constantly Googling careers, scrolling Indeed, watching videos, reading forums, asking everyone for advice, and talking almost exclusively about work and money. He stays up late researching, wakes up in the middle of the night worrying, wakes me up to discuss his fears, and seems unable to enjoy anything else.
Around this same time, he abruptly stopped taking his anxiety medication because he said he’d eventually lose insurance anyway and wanted to get used to being without it. I encouraged him to see his doctor or a therapist because medication and therapy have helped me tremendously, but he insists this is just a normal reaction to his work situation.
His mood has also become much darker. During a camping trip with friends, he barely interacted with anyone, spent most of the trip studying, and later admitted he’d been having thoughts of hurting himself. That scared me deeply. Shortly afterward, he shaved off a beard he’d been growing, immediately panicked, started pulling at his face in the mirror, said he hated himself, and later made a sudden aggressive arm movement while I was comforting him that genuinely frightened me because it was so unlike him.
Since then, the cycle has continued. Every few days or weeks there’s another career decision, another change of plans, and another wave of panic about our future. It feels like he’s living in a constant state of crisis. We’ve become emotionally distant, rarely laugh together anymore, and our relationship has suffered because every conversation comes back to money, jobs, or worst-case scenarios.
I love him very much and want to support him, but I feel like I’m watching someone I don’t recognize anymore. I don’t know if this is severe anxiety, burnout, depression, or something else entirely. I don’t know how to help someone who seems convinced the worst-case scenario is inevitable despite all evidence that we’re okay.

I’m looking for advice from anyone who’s experienced something similar. How can I support him while also encouraging him to get professional help? At what point does this become more than just anxiety about work?
tl;dr

My husband is going through a cycle of figuring out what he wants to do and I am trying to figure out how to help.