Cheating by boyfriend and false assurance of maariage

My boyfriend cheated me for the past two years...since we started relationship I doubted him as per his activity but always he shouted at me and said me that I was wrong, in 2020 I met an accident he supported me and assured me of marrying. As we were in distance relationship nad due to lockdown it was not possible for him to come down to meet but after relaxation he came to Kolkata and slept with a girl with whom he was also cating that he was in relationship. I was not aware of it . He also came to my home and met my family. Then in 2021 i went Mumbai to meet him as he was forcing me to meet me then. in 2021 August I came to know what he was actually doing behind my back. He was roaming around with another girl in Mumbai. When I asked the girl she also denied but my boyfriend accepted tht he was cheating me.. after August he again promised me to marry within coming 6 months and now he suddenly saying it's impossible for him to do so. What would I do now