3rd Baby

I am uncertain about my relationship and which way I am heading (staying or leaving). I seem to always end up staying which has been over 10 years. We have both agreed to a third child but I keep thinking about what it would be like in the future if we broke up, especially with another child. I clearly don’t want that to be my goal. Ive been ok with not being married and recently he proposed to me again. I am trying to get a clear picture of what I want. There are many things he does and I have been focussed on not making it about me. I still battle with my thoughts and feel my good qualities are wasted on him. I am never given the time of day without being cut off and never have 100% of his attention. How can I reverse this to help myself feel better? I don’t indulge in pity parties but this one keeps knocking at the door. Please help clear my mind. I greatly appreciate it.
Unintentional Model:
C: Baby
T: I want a third baby 100% but I am not sure about being with my partner.
F: Horrified
A: I doubt our relationship all the time.
R: Doubting my decision making.
Intentional Model
C: Baby
T: I want a big family
F: Excited
A: Have a third child
R: One big happy, supportive family.