[h=1]OP I understand and there are 3 scenarios that you have to work through to get your answer with your feelings.
Personally, I have been married for 26 years, and we did not arrive at 26 years with always smooth sailing on calm seas. A good marriage does not arrive at any destination without a gale or a rough sea and you must take care of the boat while upon the oceans and in harbour to make sure it is a successful journey what direction you may go. My husband and I have endured, job loss, sickness, death of family, disagreements over some things but try to respect each other's opinion, but the one thing that has held up, is our care, devotion and love for one another.
You are not selfish nor someone who is coveting. This is not about anyone else's diamond, I do know what this is about. You do not have to explain what you have done but you did and it indicates that you have taken care of him, you have put everything on the line for him, to lift him up and make sure he can in the future have a good job to take care of you and your children ( if you plan on having any). This is about his thoughtfulness, not ring size. If he had pounded the pavement and worked all he could to get you the same size ring, you would see the value in it. It isn't about the earthly value of a ring, it is about how much you are to him, your value, your worth in his eyes. We know the expectations already of who we are with as far as affordability and it is unrealistic if anyone thinks that a poor man can afford an expensive ring but we also know that someone who works hard, saves his money can buy a decent size ring.
He is your King and you want him to see you as his Queen, to be cared for, seen as worthy, loved and adored. Rings don't indicate that but what goes behind does.
Your heart is about him seeing the worth of who you are, his mate, the sacrifice that you give for him and you want him to be the same way.
I don't know if you have ever heard or read the story of Jacob and Rachel. It is found in the old testament. Jacob was in love with a woman named Rachel at first sight. He worked 7 years for her father, tending his sheep due to he had nothing else to give her. In those 7 years, it flew by and from there his love for her deepened approaching their wedding day. In the end he worked another 7 because he loved Rachel, even after enduring deceit from her father. We want a man who will put it all on the line, work for us , give everything they are to us emotionally, we want everything done in the name of love and devotion, just as Jacob loved Rachel. Some people do not marry for the intention of all for love but more of an attachement, money, pride, visibility and even political.
The story of Jacob and Rachel does go on to include Leah who he married unbeknownst to him out of deceit and he did not know till he woke up the next day, in it, he did not love her and we can see in the course of the story how his lack of love, his forced marriage, he did not care for her as a husband should for a wife. That though is another story to examine but in that , you can take away what real love does and what forced, opportunistic situations does in a relationship making for an unhealthy relationship to begin with.
To you , if you see that he cared only to get what he needed instead of giving you the best at what he could afford, you need to examine the kind of person he is. Is he there really for you, or the opportunity, for you to work for him and not for him to work for you too? 2nd Some men are just not thoughtful, have no romantic or sentimental value to things, not in touch with your feelings of symbolism in your relationship or your feelings of loving the tradition of engagement and the value of that. It doesn't mean he doesn't love you, sometimes men need to be taught that and if they did not have a raising where he was explained how to do that, well then he wouldn't know. My step dad did not understand that. He would buy house shoes at Sears the day after christmas and give them as a present to my mother. My mother would even know what he would get her. She still loved him and knew it came from his heart. It took her a few years of showing him the things she liked, how important birthdays, their anniversaries were to her and he finally got it with buying her roses or something with a sentimental attachment. The most precious was a bench with 2 squirrels carved into the bench that are loving embracing. To this day, I still hold that as one of the most precious gifts he ever gave my mother and my mother will never part with it. 3rd If you feel this is from his heart, then I know you would see the value of what he did and how much effort and sacrifice he put into buying the ring.
It's up to you to decide on the value of the ring based on his intention. I believe I know and you know too. Remember you are more precious than diamonds or gold. Look at your life and how well he treats you, is the ring an extension of how he treats you? Best wishes.