<human>: Summarize the given text in a few sentences.

24/F dating a 25/M. Our relationship has been solid for the 11 months we've been dating. We've known each other for a few years before dating and have had an amazing run of things. We talk constantly about anything and everything (work stuff, family drama, even future relationship plans such as marriage in the long term). Really very few points of contention and even those we work through amicably. I feel we've only grown stronger and I love him very much. 

My boyfriend and I always discuss our plans for the next day. Usually nothing major (errands to run, meetings to attend, etc). Over the past few months, I have heard him mention a female co-worker a couple times that he's hung out with (company outings and random weekend bar trips out with friends). I trust my boyfriend completely and have barely given any of these outings a second thought. Today, however, he mentioned in our discussion of evening activities that he was doing some errands with said female coworker. I initially thought nothing of it but as the afternoon went on, I thought that it was somewhat strange for a female coworker to go out of her way to accompany my boyfriend on a couple of errands (picking up dry cleaning, going to Sport's Authority, etc.). 

I tend to be of the mindset that men and women can be friends and not be romantically involved. However, her actions make me think that maybe she has ulterior motives.
<bot>: Boyfriend of 11 months is running errands with a female coworker. I feel conflicted about even mentioning it as it will expose my insecurity. How would you address these feelings?