Partner Completely Changed with SSRI’s

I feel like I’m spiraling mentally. My boyfriend of 2 years was put on Zoloft (dosage somewhere in the 100’s) last year and he’s a completely different person. He lies frequently, has reached out to an ex to “catch up” and hid it from me. I found out it happened recently and when I approached him about it he wanted to break up. Saying that he is miserable and did it to self sabotage because of his misery. Where do I go from that? I love him so much and know he is the one and this isn’t him it’s his meds. He is stuck right now because the meds help him with his job (he is a foreman/project manager in construction really demanding hard labor and it comes with stress) and his psychiatrist is on paternity leave so he can’t reach out to him at this moment. We haven’t had sex in months, there is no physical or emotional intimacy on his end and we live together. I also just had a medical abortion a couple weeks ago and felt completely alone and only wanted his love and attention. I feel so broken.