At what point does a depressed person's exaggerated behavior raise suspicion of bipolar disorder or mania?

My mother was bipolar.

First, there were years of depression, then inexplicable phases of shopping sprees, wasting money, overly sexualized statements, and reckless actions.

Since she also had severe psychoses at the same time as her mania, I couldn't exactly see the line between what was still mania and what was already psychosis.

A friend of mine has also been suffering from bouts of depression for a long time.

Looking back at his behavior over the last few years, I'm beginning to suspect that he might even be bipolar.

I met him in 2017. Back then, he was in a great mood, extraordinarily active, had several daring hobbies (kiting, bouldering, shooting…) and was extremely sexually active.

He wrote to me from morning to night and wanted to create BDSM role plays with me online.

I had to tell him over and over again 20 times how I would like to do it and he got more and more excited and wanted to hear it x times more.

It was almost exhausting and tiring.

We also met several times, initially for erotic purposes, later because we got along very well as friends.

Then there was a sudden radio silence, where he said he was listless and tired, couldn't get himself going and slept a lot.

He felt guilty about his inclination and despised himself for it.

Reported having to think a lot and having troubling thoughts.

A few weeks later, however, he was back to his old self and wanted to pick up where we left off erotically.

The self-loathing was gone, and he was even more inventive and extravagant than before. He simultaneously sought attention from all kinds of women online.

Then came times of emotional breakdowns, inferiority complexes, and self-esteem problems (which, however, also stem from his upbringing and his ADHD).

However, living with ADHD and the negative experiences often bring with it comorbidities such as depression or bipolar disorder.

Then he separated from his partner, whom he had kept secret, and shortly afterwards married another woman whom he had only known for a short time.

Although he had just moved into a house with his ex, it was put up for sale and while it was still for sale, the next property was bought and a new house was commissioned.

He moved from his village house to the city, tired of rural life. From there, he moved into the apartment of his newly married girlfriend. He gave notice on the apartment he had just moved into, finding city life unbearable and commissioned a new house in the countryside between the city and his old village.

There he has no one close by except his wife.

The same thing happened with cars. He first had an Audi and a sports car. Then, to buy his first house, he traded in the sports car and bought an old convertible in addition to the Audi.

Then the Audi was sold for a van, which was then too unwieldy for the city, and an electric car was purchased.

Now I don't like it because it's not sporty and I need another car.

In addition, he changed jobs several times, but this was probably due to the excessive demands caused by his ADHD.

He can afford everything thanks to the sale of his first house, a rental property, a job (which is eating him up), and a well-off parental home, and he doesn't overdraw his account, yet he still treats house and car purchases as if they were Monopoly money.

He got a burnout, but had to celebrate the wedding even though he had hardly any energy left, and the second celebration was extensively decorated with film set decorations.

Although still on probation, another car was purchased, an extremely expensive designer kitchen, etc.

Now the new job is getting on top of him psychologically, the construction site is not finished and he speaks of total powerlessness, has given up all his hobbies and is neglecting his friends.

He's definitely depressed. My question is whether this other behavior points to mania/bipolar disorder.