Losing my identity in my first serious relationship

Been dating a boy (let’s call him Rick) for about three months now and there is one issue that continues to pop up in my mind every so often. Have I lost myself in the process of achieving something I’ve wanted for so long? It’s my first year in university and I’ve done what everybody advises against: I started a relationship with someone, and moreover, I’ve started a relationship with someone who is studying the same course as me. We also live extremely close together, and this, alongside the unavoidable time spent in class together, means we are ALWAYS together. Rick is lovely and quite literally my dream boy. He doesn’t have the busiest social life however, and has no issues with spending the entirety of his week with just one person-that person being me. If I was a different girl with a different, extroverted personality type I would have no issues either, yet this is not the case. I VALUE ‘me time’ and I’ve recently become aware (as a result of finding myself in this situation) that it is this ‘me time’ that actually keeps me grounded. It appears that it was alone time and my ‘non-relationship mind’ that I learned to become myself in, and now I don’t have access to a single and independent life I think I might be losing myself. I often get racing and anxious thoughts about the permanent and imminent loss of my entire identity, and sometimes convince myself that for the past three months I haven’t once truly felt like myself. Alongside this issue is the fact that I have simultaneously, in the past two months, developed a series of anxiety attacks and sometimes 3 day long bouts of depression. Although these are mostly unrelated to this specific problem I often wonder if I would be experiencing them if I had never ventured into this relationship.

On a final note: Rick is certainly not aware of how deep these feelings go. Since his childhood he has had severe insecurities and anxiety surrounding abandonment and rejection and although he can’t help it, this adds a whole other level to my problem. I feel like if I told him the truth it would deeply offend him and send him into a spiralling depression of some sort.

Kinda freaking out about this. It’s freaking me out because I have always wanted a boyfriend and it saddens me that this is happening in my first serious relationship. If anyone has ever experienced something similar to this, or has any advice I would be so grateful.

Feeling quite lost.