Struggling with the New Custody Schedule

Got the papers finalized last month and we're on a 50/50 split now. Every other week with the kids. I was prepared for the legal stuff but I wasn't prepared for how hard it is to drop them off at their mom's house every two weeks. My oldest asked me last night if I was leaving them. Man that broke me. I know this is better for them in the long run but those transition days are killing me. Anyone else dealing with this? How do you guys handle it mentally?