Splitting time with father advice

I think my partner and I are on the verge of a breakup. We are living in a loveless relationship and it’s been taking a toll for a long time. I think the only reason I’ve stayed this long is because I don’t want to be apart from my kids. They are literally my entire life and I don’t know what to do without them. They need there mom! If anyone has gone through a split can you please give any advice or experience you have with how to help the little ones through it and how to survive yourself? My babies are 3 and 9 months.