My partner and I have been together for 25 years and about two years ago we became monogamish. We have threesomes/foursomes every few months and it has been great. We have no issues in our relationship. I trust him and vise versa. However, we’ve been talking to a new woman whose body is very different from mine. I’m full figured and she is much smaller. I know my partner loves me and is dedicated to our relationship. He is absolutely amazing and has never given me a reason not to trust him in all these years. However, I’m struggling with insecurities about our body differences. I’m attracted to her and he is too. It seems like she is attracted to us as well, so why am I feeling this way? Please give me some pointers to get beyond this so I can enjoy the experience.