Let's paint a picture here of such a relationship for more detail.

Let's say that you've been dating a guy for a while and you're planning on getting married soon. He's pretty reserved with you regarding intimacy, affection, and romance in general. He gives you light kisses sometimes, but never any intense make-out sessions or anything like that. He'll cuddle you if you ask for it, but he's generally not a huge fan. At night, he prefers to sleep in a separate bed rather than with you, because he finds it uncomfortable to touch for extended periods of time. He buys you flowers and gifts on special occasions (e.g. Christmas, Valentine's day, your birthday), but beyond that he doesn't make any grand gestures of romance because he's "not a very romantic person". In a similar vein, he never compliments you on your physical appearance at all. Your sex life with him is also somewhat sparse and vanilla, though nothing out of the ordinary- he initiates sex once every 2-3 weeks, he's missionary-only with zero kinks, and during sex he seems to be enjoying it but without any enthusiasm or intensity.

Your entire relationship has been pretty lukewarm like this- there was never a "honeymoon phase" where both of your were crazy for each other. However, he insists that he loves you and wants to spend the rest of your life with you. He tells you that all his ex-girlfriends have been "crazy", while you're very stable and down-to-earth.

Now, it comes out to you that he wasn't like this at all with a previous partner. With his previous girlfriend, who was significantly more physically attractive than you, he was very enthusiastic with touch, intimacy, and affection- he would constantly kiss and cuddle her, touch her affectionately, and compliment her all the time. He would frequently buy her expensive gifts, spontaneously take her on lavish vacations, and make very many grand gestures of romance towards her. In addition, he had a very wild, adventurous sex life with her, and would do all kinds of crazy sex acts multiple times every day. The only reason this relationship ended was because she dumped him after being forgiven for cheating multiple times.

When you ask your boyfriend about all this, he tells you that back then he was immature, and he's grown since this relationship. Now that he's a mature adult, he doesn't care about constant cuddles/intimacy, frequent hot sex, or grand romantic gestures; instead, he cares about common life goals and financial/emotional stability, which is why he dated you.

How would you feel in this scenario? What would you do?