I’m a 25-year-old man, and after five years, I no longer feel attracted to my partner, who is 24. Should I consider ending the relationship?

I've been in a relationship with my girlfriend for nearly five years, and she truly is a wonderful person. We share many interests; she’s athletic, excels academically, and possesses a kind, caring nature. Like any relationship, we've experienced our highs and lows, including some significant disagreements, but I believe these conflicts are fairly typical. However, this is my only relationship, so I may not have the full perspective. I realize that part of my struggle comes from a fear of loneliness and the idea of giving up on someone who has been such a positive presence in my life. I feel torn because deep down, I believe I should be exploring other options at this stage in my life to understand different perspectives and determine my preferences for a serious relationship. Compounding this is my high sex drive, which has created tension in our relationship, as I'm not very affectionate otherwise, except when it comes to intimacy. There are times when I feel guilty for only initiating physical touch in that context. I genuinely enjoy discovering new experiences with her, and I cherish the time we spend together, whether traveling or engaging in activities we both love. I have many wonderful memories with her. Nonetheless, there are periods when I contemplate whether we should break up, contrasted with times when I feel immensely grateful for her presence. Just yesterday, I felt frustrated when she walked through the door and I wasn’t attracted to her at all. It seems we're approaching a stage where marriage and children are on the horizon. I often think she would make a fantastic mother and life partner, yet I also struggle with my current lack of attraction, which is affecting my feelings toward her. For some context: - We don't live together; she resides with her parent and siblings while I still live with my own parent. - She is currently studying, whereas I just completed my studies this year.