It's getting really hard to keep Omicron away. A surprisingly large portion of my friends who have taken reasonable safety precautions have come down with it anyway. New York seems to be at or near a peak, with an astonishing 10% of people in NYC estimated to have it right now. Almost every event I'm aware of from the last few weeks had to send a email saying "we're sorry to inform you that you may have been exposed..." a few days later. We had an exposure in our house shortly after Christmas, where the care person for my partner's mom tested positive and had symptoms the next day. Despite spending an entire day in the same house with her, none of the rest of us seem to have caught it. That was probably luck; viral load can vary tremendously, and she probably had a low viral load.
So far my friends' cases that I know of have been mild, which has been good. If you're young, healthy, and vaccinated + boosted, you're likely to have a mild case. However, there's going to be a strain on our hospitals over the next few weeks, mostly from people in high risk categories or who aren't vaccinated or boosted yet. Omicron is sufficiently different from the original strain of COVID that the vaccine was designed for that even the original two-shot vaccine course is not great protection anymore. (see attached figure from the UK showing the vaccine effectiveness against symptomatic illness for Pfizer with either a Pfizer or Moderna booster) For hospitalization risk, the UK report annoyingly lumps the AstraZeneca + Pfizer/Moderna booster group in with the Pfizer/Moderna + Pfizer/Moderna booster group, but it does report an 88% vaccine effectiveness against hospitalization for those two groups against Omicron compared to 52% for people who haven't had a booster yet. I'm so glad we have tests, vaccines, and boosters already; if this version of the virus had hit us anytime in 2020, this would have been a worldwide disaster of epic proportions. If you haven't had your booster, go get it ASAP.
Even if you are boosted and in a low risk category, you should probably avoid scenarios where you are in close unmasked contact with a significant number of people for a few weeks. Severity of infection can depend a lot on the initial viral load you're exposed to, and that viral load varies tremendously over time and from person to person. One person with extreme viral load can easily infect 100 others in a crowded bar environment, and you do not want to be the person who spends an hour next to them. (Recall that the Wuhan doctor who first sounded the alarm on COVID died of it even though he was healthy and in his 30s; he probably got an absolutely stupendous viral load, and his immune system never had time to catch up.)
If you want to reduce your chance of getting Omicron after getting boosted, you'll want to have everyone you hang out with unmasked/indoors take a rapid test, and you'll want to have an N95 for any shopping outings.
We're unfortunately in the situation where we have both an old person and an infant in the house, and if either of us gets COVID then we lose our support staff and we are sick and we're at risk of infecting the high-risk people in our house. We are now testing everyone who comes in every day, and we're burning an unholy amount of money on PCR-grade Cue tests. My partner and I have separate bedrooms, and we stayed masked when outside our bedrooms for the last few days in case one of us but not the other was developing a viral load. Fortunately it didn't come to that.
There will likely be a brief but intense peak in caseload over the next 2-3 weeks, followed by a strain on the medical system. We'll probably fare better than most of the rest of the country, and what happens to the death rate in New York over the next week will be a good indicator of what to expect for the rest of the country in late January.
At some point we'll hopefully get to declare a variant "just the flu" and get on with our lives. In areas with very high vaccination + boosting rates we're almost but not quite there; the high rate of infectiousness will still result in a strain on the medical system even though most cases will be mild. In parts of the country with lower vaccination rates, it's likely going to be a shitshow with overloaded hospitals when Omicron takes off there in a few weeks. It's possible the large number of prior COVID cases in these areas will make it less bad than I think, but I haven't done a deep enough dive to have a more confident opinion on this.
So many of us have worked so hard for so long to avoid COVID that I've noticed some people treating catching COVID as some sort of moral failing. It really isn't. Don't beat yourself up over it. The only moral failing is knowingly exposing other people without their consent when you're sick or positive, or failing to notify people you've been in contact with recently if you test positive.