Handling myself on my own as a young woman?

I’m not sure if this comes with being an attractive woman or just being a woman in general…....I’m not saying that to sound mean, self centered, or arrogant so just hear me out.

I don’t live in the “best” of areas. It’s not bad, no serious crime or anything, just a good chunk of ghetto people. I grew up with a very different background, so I tend to carry myself in a nice manner. I try to dress nice, speak properly, etc. The problem is that I feel like I draw attention. Lately, I’ve been almost afraid to go and run errands on my own because almost everytime I do, I get hit on by at least one loud egotistical person with no concept of boundaries. When I go out with my boyfriend, I do not have any problems but naturally I can’t be with him all the time. I want to be able to do things on my own, but when people stop and try talk to me and follow me around it makes me really uncomfortable and I don’t know what to do. I want to be nice (because the times I wasn’t I was called a bitch or they just try that much harder) but at the same time I just really would rather be left alone during my errands.

For example, just yesterday when I was mailing a package at UPS, I literally had a guy first try to talk to me in the parking lot as he was looking for a parking space (I was walking from my car). He drove off to find a space and I walked into the UPS thinking it was over. But no! He then comes into the UPS store (it was obvious I was going there because of the giant box in my hands) and came up to me with a card. I didn’t say too much because I thought he’d just leave the card and go. But he was too close, as in close enough to be against my shoulder and body (even though I was trying to move away), and then said “wait you’re not gonna call me from a card let me put my number in your phone” and tried to take my phone from me! Before he could I snatched my phone away and said “I have a boyfriend sorry” and just looked away. He then huffed and left but come on! That’s too much! All while the man behind the counter just watched! This happened very quickly so I just didn’t even have time to really think.

Something similar happened at the mall last week with a person being too persistent and too close to me. He didn’t go so far as to try to take my phone, but still…...when these people ask to pump my gas or carry my things or just try to talk to me, I just feel so uncomfortable. I don’t know what to do. It’s not like I’m attracting this attention because I’m dressed to draw attention or anything either; I was wearing a long maxi dress and a vest. I don’t tell my boyfriend of all these situations (only some of them) because he’s very protective and will get upset about something that he can’t even do anything about. I feel like I should be able to go out during the day and do things on my own but lately I’m just afraid to. I hate feeling like this…...Any advice? I never know how to handle these situations because saying I’m uninterested or that I have a boyfriend rarely actually deters the attention….and yet if the first thing I say is “I have a boyfriend” I am apparently thinking too highly of myself and making false assumptions. This just happens to me a lot and I want it to stop :/