I think that you should introduce your boyfriend to your friends so when you see them, he won't wonder where you are and who you are seeing. Take him once to meet your friends and he'll feel good about it. If you tell him you're going to see Mary or Betty, give him their cell phones. After he sees that you are actually just seeing your close friends, he probably won't have an issue with it. I think any man will wonder about this if you don't introduce your friends. Hopefully you know his friends too.
Another option is to invite your friends to his house and just have dinner with them. Ask them to bring something for a potluck. That would be fun.
I think rushing into marriage is not a bright idea. You need to know him better. I do think 2 years is enough time to know if he is controlling or what. It's hard to tell if he's actually controlling just by that incident.
I think that he will be more comfortable and will trust you more if he knows your friends too.
Getting married is a great thing but you need to marry a good one this time with the idea that this will be for good. Take care and be patient with him.