Was I the asshole for my ex-wife's sake?

I was married to Jane for seven years. We had a good life together, bought a house, got pets, did all that grown-up stuff until we decided it wasn't working out and parted ways amicably last month. It’s been tough being single again but I’ve been focused on myself, gym sessions, meals for one. Then, there was him. We met through a mutual friend at his birthday party. He’s cute, has that runner’s build. I knew he fancied me the minute I walked in. One night, after a particularly long week of clients and feeling like an island, we ended up talking late into the night. Before you know it, alcohol lowered my inhibitions. We decided to hook up, no hard feelings, no expectations, just one night of fun. Fast forward, we’ve been seeing each other behind closed doors ever since, keeping our affair a secret from everyone including Jane who’s still processing her divorce. I’m torn between wanting to be with him and respecting my ex-wife's feelings. Was I the asshole for choosing me over her? What do you guys think?