It's relentless. I get that. I found that age a bit awkward. Old enough to do more with but never really seem that into it. It does get better. I say about 18 months to 2 years its easier when they talk more and you feel like you have company. At 3, as much as it sounds twee, I have my mini best friend. I mean yes its challenging in new ways (tantrums) but generally she's fun to be around.
Things we do /did
Kids cinema showings. Toddler time they're usually called. Usually in the morning. You can take your own drink and snacks in and have 30 mins to yourself (ish). They're very relaxed so no need for good cinema behaviour. Our local one is £3 for the two of us. We combine with a wander to a coffee shop after and the library or the works for a cheap book. Or the park after.
Softplay. Yes its busy. But not so bad if you have one with a good toddler area. Get there early and you can get an hour or so before its insanely busy.you have to play with them, but i often had some nice chats with parents in the toddler area because theyre probably as bored there as you!
Swimming. We do swimming on a sunday often. Goto the cafe in the pool, next door to the library. Its a good few hours gone and used to ensure a good nap!
Forests ans national trusts. These can seem more lonely solo. But a good hour or so out. I used to walk them alone with a young baby. Someone always used to chat to me. Kids encourage conversation in most people.
Look up your local children centres and libraries ours do some saturday morning sessions. Story time and the like.
Play towns. Little city and similar. Many do have weekend sessions. 16 months is getting to point they'll start to get it. One to think about over next few months. Also play cafes. We have an excellent one near us. Often have solo parents in there on weekends so always get chatting to someone.
For 5 minutes peace to yourself. Look up setting play things at home. We got a flisat table from ikea. At 16 months you still need to supervise a bit but you can use taste safe things in it. I someones do something really easy like a box of slightly stale cereal in, some diggers and apoons and cups. Put a table cloth on the floor underneath for easier clear up. Can also stick playdough in with cutters etc. Make taste safe if needed. Although at first they may not spend ages on it it improves over time. It used to give me a good 15-20 minutes. Now i get an hour.