R.K.
I'm in the same boat that you're in. I have a 5,3, and 6 month old as well. After a while you start to feel like your brain is turning into mashed potatoes from lack of use. I did the MOMS club thing which was nice for a while, but then I got sick of talking about my kids all the time. How many teeth does your baby have? BLAH, BLAH....same ole thing. I could never get past the superficial questions. I did make one really good friend there which was worth the experience, but dropped MOMS club when I realized it was mostly for new moms.
I'm not sure what the solution is, but wanted to let you know you're now alone! I'll keep reading the advice you get for me as well. It would be nice to have conversations again that don't involve children, poops, and dinner time.