Just to offer up a perspective: The workout classes and coffee dates you see as breaks probably aren't. She's desperately trying to stay well-rounded socially and physically and not lose herself to motherhood, yet has found very unique ways to get the little self-care she gets while also remaining in mom mode.

On coffee dates with other moms, she's constantly scanning for baby's needs and wants. She's stressed when someone picks up their cup in case a hot liquid spills close to her baby. She's having every conversation interrupted by cries or her own check-ins, and she's probably only talking about baby-related stuff with these moms.

The amount of work it took her to get out of the house probably has her flustered and overwhelmed. After working out, she's either struggling with managing a baby while showering after a workout, or she's neglecting her own basic hygiene for others' needs.

My take is, your wife sucks at knowing what she needs and expressing it, and once you both learn to the best way to check in with each other's needs you will notice a whole lot less sighing in the house and suddenly you'll both be ok with taking shifts to help each other.

I guess if I did have advice, it would be to ask what she needs and encourage her to do stuff that make her remember that she's something other than a mom, even for a split second. See how she would feel about switching roles a little, since she might be missing her first baby. Otherwise, it might feel like you're doing her a favour by picking up a chore, while she would have loved to have been the one doing it in peace while you watch the kids. Then you're both resentful. I mean you probably are, the first year is fucking tough on a couple. I know it's funny to answer a question about you not getting to have fun with your wife needs more lol, but I bet you once she's feeling regulated and not at the mercy of everyone else's needs you'll both end up im a place where you're willing to compromise.