I'm (28m) feeling insecure about my gf (26f) and her close male friend

It started when I met her friends. I live in a different town to my gf and most of her friends. When I told them where I lived, one of her friends, Eric, then turned to my gf and said ‘ooh you can kill two birds with one stone’ in a suggestive way. It turns out that a different guy friend, Simon, lives in the same town as me. I found this strange, as the tone of the remark from Eric seemed suggestive. Eric told another joke about my gf and Simon the next time we all met. We were all going out in my girlfriend’s town for her birthday, so Simon wouldn’t be able to stay out late after the buses and trains stop, unless he could sleep at someone elses. So Eric jokes that Simon could stay at my girlfriend’s house, with I’m pretty sure a suggestive kind of tone. Again, I didn’t like the joke, but it got lost in moving conversation so I didn’t point it out at the time. I mentioned the jokes to my gf and she said she hadn’t really noticed them but was very supportive, she said Eric was being rude and she would tell him to shut up if it happened again. She also said there was no history with Simon and could think of no reason for the jokes. The jokes made me uncomfortable but I was reassured by what my gf said, there was no past or present thing between her and Simon that would make sense of the jokes. Maybe Eric is just a stirrer, and he does seem the type, or maybe he personally would like my gf to be with Simon, perhaps to keep the group strong and not have her drifting off or something. It’s very possible that the other things I will mention now are just me being hyper vigilant because of the stupid jokes, seeking out things to worry about. But here goes. There were some possible things of concern from my gf. The first time I met her friends, we all went out and she did seem particularly prone to giving Simon attention and laughing at his jokes, in my opinion, somewhat uniquely hard. She seemed to take most opportunities available to say things to him, like when they were all having a laugh by showing bizarre videos on their phone, she said to Simon “bet you didn’t search it, its just on your phone already”. Things like that, which arent in themselves flirty, but she seemed to take most opportunities to say something to him. More than with other people anyway. We were walking home from the night out, where we went from bar to bar, sometimes new and sometimes different. It was apparently a game that Simon made up and she said “I don’t want to admit its a good idea, or he’ll get a big head”. When we got home, the conversation eventually moved onto hay fever as I had bad hay fever at the time, and she mentioned how Simon got the worst hay fever ever while they were on a friends group holiday. She showed me photos from her phone of him with very red eyes. To be fair, it was a funny story etc and related to what we were talking about, but at the time, even on first meeting the friends, I was getting a bit frustrated with these small things. I do have a tendency toward paranoid jealousy though. Do remember that I’m listing these things but its not like she keeps talking about him and talking with him, its just that these are the things that I have zeroed in on. So another example. Her male friends were on a reality tv show as teens, and there were funny awkward moments and the novelty of it being her friends, so we watched some of the episode. She definitely reacted very uniquely when Simon was on screen. It sticks in my head even now how she reacted. She got loud and mentioned how he ‘still has that hat!’. There was another time when we came across a friend of hers while we were walking back from the train station in my town. This friend of hers, who lives with Simon, asked why she was in this town (as I’m holding her hand). “Have you come to see Simon?”. It’s a small thing, but come on, I’m holding her hand… Anyway later, on the bus back to the train station for her to leave, she says that Simon messaged her saying he heard she was in town. She joked “im talk of the town”. I personally wouldn’t bother texting a female friend just because they are in the town I live with their boyfriend. It's not like the towns are really far apart, just a 10 minute train. Skip to last weekend and we go out for a birthday of a female friend of hers. Again my gf shows Simon a lot of attention. Before her attention moved to me, by far most of her remarks were directed at him, and laughing very hard at him, and at one point she briefly slipped into the cutesy voice we use amongst ourselves, to him. It was like a slip of the tongue but that bugs me. There was one point where they were talking about tv shows and two of us were standing there not being included in the conversation. This was only for a short time, but it got to me and I was visibly uncomfortable. She then kept asking what was wrong and I was embarrassed to say. From that point she was clinging onto me and giving me basically all her attention. Do take note that she is so sweet and nice to me, none of this is her being rude or inconsiderate. This weekend, after that pre-drinking, we ended up getting out of the taxi early and coming back to mine without going out to town, so there was no more signs. I mentioned the cute voice moment when we were very sleepy that night in bed. I spoon fed her the answer though, as I said “it was funny that our cute voice slipped out in you tonight. I just hope your friend didn’t take it the wrong way. I know it was misdirected” and she said yeah it was misdirected and they probably didn’t even notice. I didn’t say his name, neither of us did, I didn’t want to come across as insecure and increase his status in her mind. But she didn’t ask ‘who did I use it with?’ or anything. I dunno, I feel slightly that it was insufficiently talked about. I really can’t stress enough that everything else is GREAT between me and my gf, like the best connection either of us has ever had, and we have both said that. We've been together for 3 months or so but it feels so strong already. These tiny things are scattered amongst an otherwise perfect connection, and its taken my proneness to be jealous and some likely hyper vigilance to see them. But basically im now in this path of thought that is hurting my pride and confidence. I don’t know how to mention it to her or whether to mention it at all. I’m scared of appearing insecure and possibly fanning any flames of some attraction she might have for him. I also don’t want to make things awkward when we hang out with her friends. I don’t feel threatened that she will leave me for him or anything like that. Its an issue of pride really. He could be a brother figure to her, she has known him for ages. But I don’t know. Shall I mention it? And how can I go about mentioning it without pushing her away/towards liking him, as the case may be, more?

Listen Jean, I want to talk with you about something that I have been thinking about But I am afraid of what you will think about it. Is it ok if we talk about that now? Well, I am quite hesitant because I don't want to seem insecure. However I noticed that there's something going on with you and Simon and to be frank: I'm a bit jealous. And then you STOP talking. And only ask questions. And you don't listen to the answers, you only watch her closely. Good luck