Most Helpful Guy
I think that flip flopping crap happens at every age. Let me answer your question like this: it's all about the context to what he's in touch with you about.
Casual: "Hey Monica, do you want to grab drinks later?" It's a short term plan, it gives him a chance to interact with you on a quick and seemingly meaningful level, where your guard will be a little bit lower than it might be otherwise. But you'll note how the way he's interacting with you isn't about YOU it's about having drinks, with a woman who happens to be you.
Committed: "Hey Monica, I saw an ad for a Jazz concert happening at such-and-so park tomorrow night, and my wine collection is just getting too big for my kitchen. If only someone could help me free up some space..."