Originally Posted by london
What I guess I want is things that I can ask him to do to make me feel that he does value me and I'm not dispensable because if I'm going to carry on with this, I can't stay this insecure. I just can't. Any suggestions of concise steps he could take to show (her as well as me) that I matter, or even that the other people he sees, whoever they are, matter? If he chooses not to take them, at least then I know my feelings are not important and I can move on. He is so willing to talk and reassure me verbally, that I do believe that they are but then other things counteract that, somewhat, and I'm left feeling confused.
I would say that you have framed what you are looking for exactly opposite to what I would recommend. This post is about what your bf is doing or not doing, what his girlfriend is doing or not doing, and how they need to be better at reassuring your insecurity.
You are currently dating a person who you've known for a very short period of time who is in a very unsteady monogamous relationship with someone he hasn't known very long. The best step for me
would be to slowly back away from the explosion to come, because the odds of this working out as a healthy relationship between me and another fully functional adult are basically 0%.
However, I get the numbing power of new love and I understand if you still choose to dive face first into this situation. That being the case I would *still* recommend not framing the problem around what your boyfriend needs to do to console your insecurities. They are in no way responsible for your feelings of security. You are responsible for your feelings in every way - in this particular instance I think you'd be short sighted to ignore these instincts because what they are telling you seems to be pretty accurate (RUN).
Failing all of that, if you must get into these people negotiating how to navigate your feelings for you, I would suggest setting up a calendar. YOU set up a calendar with YOUR time. Share it with him (and her if she requests it) so that he can decide if he wants to 'claim' some time with you or not. You put on there the times that you are available, he sets up an event on your calendar 'claiming' some time with you and viola.