I’m really sorry to know you’ve lost someone so deeply special to you. That’s always a hard thing to recover from and I think you’re strong to be able to carry on.
About your questioning here though…so, initially it’s important to know that CGL is not BDSM. Caregivers are not default dominators, and the act of caregiving is not the act of domination or control. Littles are not default submissive, and regressive personalities, moods and interests, do not necessarily mean the person is under submission to another or must act submissively to be fulfilled. While some individuals may also be a part of the BDSM community we all are not, and CGL by itself is a separate grouping based on personality and not sexual interest.
Next thing to know is that a Caregiver is an individual who generally feels comfortable with expectations of adulthood, has the desire to "take care of" their romantic partner(s) more than typically expected, and often presents as naturally parental by personality regardless of age or experience as a parent. Caregiving is an act of romantic love, and not all people show their love in this way. It’d be unfair for your partner to demand you show your love for them in this way if it isn’t how you communicate it naturally. If this isn’t you then it just isn’t you and that’s okay. You aren’t limited to how you love, and your partner can potentially learn to understand and appreciate how you love.
Though, Littles don’t require Caregivers and calling someone “Mommy” doesn’t necessarily mean too much. You may be able to set boundaries and outline what you will and will not accept or do, and even if you accept being called “Mommy” it doesn’t mean you must act as a Caregiver. He doesn’t need
a Caregiver, and you don’t need
to be a Caregiver to have a successful, fulfilling relationship.
It all boils down to initially having that first conversation, and making it clear in the ways you are comfortable and happy showing your love for your partner. Relationships do take adaptation so you two may need to learn to adapt in some simple ways that are both acceptable for you two. You’ll just have to talk about it openly and honestly.