How to stay in love/loyal?

Due to some family related issues, I’m banned from ever seeing my S.O. for 3 years but he’s more than willing to wait that long for me. My problem is that I don’t have faith in myself that I can wait that long.

I mean I love him with all my heart but I also have a tendency to fall out of and fall in love very quickly so I’m scared I might not stay in love with him for the duration of the 3 years. Especially since I’ll be in a new school and might meet new people that will interest me 😞

Any tips in staying in love and loyal and faithful?