A few things to think about:
Environmental Studies and Environmental Sciences are different, if you choose to go that route rather than psych. Here is a simple comparison of differences between E Studies and E Sciences https://envirosci.wisc.edu/environmental-sciences-vs-studies/
Wesleyan offers an Earth and Environmental Sciences major https://www.wesleyan.edu/admission/academics/splashpages/ees.html
and Environmental Studies as a linked major https://www.wesleyan.edu/admission/academics/splashpages/envs.html
Middlebury only offers an Environmental studies major http://www.middlebury.edu/academics/es
Look at the professors and annual course options in all of the above departments, perhaps one will be more appealing than the other.
Wesleyan has 3,000 undergrads and is around 12% international, Middlebury around 2,600 and around 10-11% int’l, so there will be more international students at Wesleyan. IMO if you are extroverted both schools will work, if introverted I would give a preference to Wesleyan. But those considerations should take a back seat to your preferred academic offerings.
Have you taken the virtual tours of both?