I think my boyfriend is cheating, what can I do?

So I'm freaking out. I had a weird feeling and he seemed to be hiding something so I checked his phone while he was sleeping (I know it's wrong) and he has Tinder again. I looked at it and he has a ton of matches, some he's talking about fwb and others he's asking how to ask them out. I should've looked at his profile to see what it said but I didn't. I also saw that he made a separate Instagram profile and is following a girl (and only her). I'm supposed to go on vacation with my family next week and while I'm gone (since we live together) I'm scared he will be going out with these girls. I love him so so much is there anything I can do to fix this?