Hi folks, I'm (35M) new to ENM and could really use some advice from experienced folks... It's a long read so please bear with me:

Around 9 months ago I met "Emma" (34F) who took an interest in me. Emma has been monogamously married to her husband "Paul" (43M) for a decade and have 2 beautiful children all living together. I was told they are brand new to polyamory and that Emma wanted to find just one more partner to date in her life (me).

When Emma approached me I was upfront that I had just gotten out of a 13 year monogamous relationship and wasn't ready to date anyone seriously but was open to seeing where this goes so long as it feels right for everyone. From the start I told Emma and Paul -- since they are each other's primary partners -- that I would then be my own primary partner, where the majority of my energy will go towards self development. I also said I would like to have the option of dating others as well which she agreed to. As a personal boundary I said if I ever started to feel like I am becoming a distraction to the family that I would check myself out of the relationship.

After spending a couple months together it quickly became apparent that although Emma and I had great chemistry, she was way more into me than I was with her. I reasonably understood that the allure I had most likely came down to Emma having spent the last 5 years nursing children, and I am her first taste of a unique experience with someone who lives a fun and leisure bachelor life style and more emotionally available than her overworked husband who I learned has never been the most emotionally attuned in the ways that she needed.

Now here are the problems I noticed:

1. Emma is amazing in every sense of the world and I feel indebted by how much love, care, and support her and her husband has provided me during my separation with my ex. My relationship with Emma has gotten to the point where Emma wants to have my babies and dreams of all of us one day all living in the same home as two families together. Emma's entire family are lovely in every way but I just doesn't feel like integrating into their family is right for me. I am not ready to have children of my own in the foreseeable future. And if I did start my own family I wouldn't want to be with a partner who already has their own immediate family to take care of.

2. Emma's relationship with her husband is shakey and I feel like I am being used as the way "out" of their marriage. I came into this relationship dynamic with the understanding that her and her husband were completely solid -- in love and securely attached to one another -- but it wasn't long until I started realizing I was doing much of her husband's emotional labor for him and the result is Emma fell deeply in love with me in a very short time due to this massive deficit she had in her relationship. I recently learned Emma and Paul has stopped having sexual intimacy with one another, and by the sounds of it are no longer romantically involved. Paul's got a new partner "Jen" and Jen has coming over every weekend to help with with their kids and spending lots of intimacy time together with Paul. From speaking with Emma it seems they see one another as good coparents and co-home partners, but sex and romance privileges seem to only be reserved for Jen and myself. This makes me worried because it now puts a lot of pressure on me to "be that person" in her life where that role should've been at least PARTIALLY fulfilled by her husband. I didn't sign up to take the place of her husband for romance, intimacy, and emotional labor. I signed up to be someone that adds something to her life, not someone that replaces someone else (Paul) in her life.

1. I still want to date other people (and have been upfront about this) -- I would like to date poly people -- so I can continue my relationship with Emma -- but am also open to mono relationships where if I find someone who is more compatible long term I cannot promise that I wouldn't leave Emma. The problem is Emma only wants to date me, and have expressed that she would likely get jealous if I started seeing other people. She said she'd learn to deal with it, but my gut says she wouldn't be happy and it would hurt her. She's also expressed that if I ever decided to have children and start a family with someone else it would be really painful for her because she would wish that person would've been her. That is way too much pressure for me, and at the same time I feel shitty because if I did find someone more compatible it feel like I used Emma as a placeholder "until I found someone better". I'm 100% she would feel that way as well. From what I can tell she likes me so much she's willing to consent to being a relationship doormat, but I know for a fact it's not going to end well.

I should note again that Emma is an absolutely amazing partner and mother. If she was single I would've easily imagined myself starting a family with her. Hell, I'd want her to be the mother of my children if she didn't already have her own family already -- and if not -- then at the very least hope to have her as an anchor/primary/nesting partner which is also not possible unless I move in with them (don't want to).

So what are my options? It's in my hands but I feel like telling her all this might be a death knell for our relationship -- which can be a good thing long term like tearing off a band-aid because of incompatibilities but still sucks short term.

Alternatively I tell her and she pretends like she's okay with me dating other people, but ultimately gets hurt because it sounds like she wants a monogamous relationship with me that I simply can't promise which seems like it's just prolonging the pain?

I'm not sure what to do but any insight / advice / similar experiences that can be shared would be greatly appreciated.