This is such a thoughtful thing to ask about. You sound like a lovely friend!
One thing to bear in mind about the whole process is that the numbers tend to drop off at each stage. So, someone might get, say, eight eggs (random number for the purposes of this discussion) - the mistake some friends and family may make at that point is to think of that as, basically, eight babies. But in practice, then comes fertilising them - let's say six fertilise. Then the lab cultures them for a few days. By day 3, maybe one isn't progressing but the others are still hanging in there. On to day five, let's say maybe there are three blastocysts at varying levels of quality, and one more that's behind the others. So, imagine the best one gets transferred - then eventually you get through the lab report telling you they've been able to freeze just one of the others, as the remaining ones weren't of suitable quality. And then you have to wait and see if the transfer works, which they don't always. So, you've gone from eight possibilities down to two, max, over the space of less than a week. (And this scenario doesn't incorporate things like PGS testing, which some people may have done at part of their treatment and which, again, can cause a big drop off in numbers.)
Don't necessarily pay attention to the specific numbers above - I pulled them out of thin air to illustrate the bigger point, which is that as a process, it tends to be pretty brutal with lots of stages along the way where it can all go wrong. Every time you get through one stage, and get your head round one set of numbers (whether they're better or worse than you'd hoped for), you're then straight on to waiting for the next set.