So alone in 10 year relationship

I have been feeling increasingly miserable, sad, and lonely. My partner and I have been together for ten years and he proposed three months ago, but recently I have been struggling with a lot of doubt and sadness.

My partner works most evenings and many weekends. I understand that he enjoys his work and that things are very busy for him, but I have been feeling like I don’t get enough quality time, connection, or shared experiences with him. I do have my own friends, family, and exercise, and I try to make plans and do things, but I still feel lonely because I miss experiencing life with him.

Something I am struggling with is that the sadness doesn’t only happen when I’m alone or when I’m thinking about the relationship. I feel sad most of the time, even when I do try to go out, see friends or family, or do things that I would normally enjoy. I often find that I can’t fully enjoy those moments because I still feel low inside. When I look back on things I have done or memories we have made, I often don’t feel happiness or excitement,  I feel sadness or regret instead.

When I try to express with him that I’m feeling lonely or wanting more time together, he often responds by saying things like, “What do you want me to say? I’m stuck between a rock and a hard place. I’m sorry it’s manic at the moment.” I understand that he feels under pressure and that his work situation may be genuinely difficult, but I often come away feeling unheard and as though my feelings are a burden. In the past we both agreed to spend less time on phones before bed and actually talk to each other and to make time for one date night a week, but this time he doesn’t even seem like he can be bothered to do that. I think he’s fed up with me being miserable so is pulling away from me and not wanting to spend any time together.

The proposal has also been something I have been thinking about a lot. I know we have been together for a long time and that he chose to propose, but if I’m honest the whole engagement and planning a wedding hasn’t felt exciting like everyone says it should be a time to enjoy. Because we’ve barely spent any time together.

I have been crying a lot and feel miserable most of the time. I would like help understanding whether this is mainly about the relationship dynamic, whether I am experiencing something affecting my overall mood, or whether both things are contributing.